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									Bk   Num   Ans                           Question                               Answer A             Answer B              Answer C             Answer D           Illustr
                 As shown in the illustration, which of the listed types of Across-the-line       Capacitor            Auto-transformer     Part-winding
12   1     C     motor controllers and starters is indicated?                                                                                                     EL-0012

                 You are performing an out-of-circuit test on the semi-      A low reading with   A low reading with   A low reading with   A low reading with
                 conductor shown in the illustration. Using an               red lead on "A"      red lead on "A"      black lead on "A"    black lead on "A"
                 ohmmeter on 'low power' setting and with leads              and black lead on    and black lead on    and red lead on      and red lead on
12   3     D     properly inserted, which of the listed results would        "C"; and a high      "B"; and a high      "B"; and a high      "C"; and a high       EL-0068
                 indicate a good Emitter-Base junction?                      reading with the     reading with the     reading with the     reading with the
                                                                             leads reversed.      leads reversed.      leads reversed.      leads reversed.

                 When troubleshooting most electronic circuits, 'loading input impedance          input impedance sensitivity of less       sensitivity of more
                 effect' can be minimized by using a voltmeter with a/an much greater than        much less than the than 1000              than 1000
                 __________.                                             the impedance            impedance across ohms/volt                volts/ohm
12   4     A                                                             across which the         which the voltage
                                                                         voltage is being         is being measured
                                                                         measured

                 On a vessel with turbo-electric drive, which of the         Excessive            Tripped main         Overheated           Closed contact in
                 following conditions would indicate that the propulsion     vibration of the     motor interlocks     crosstie busses      the field circuits
12   5     A
                 motor had dropped out of synchronization with the           vessel
                 propulsion generator?
                 On some diesel-electric ships, the DC propulsion            rotating brush       raising the          lowering the         decreasing
                 motor will only attain half speed when the generator        alignment            generator engine     generator engine     excitation
12   6     B
                 fields are fully excited. Speeds above this are obtained                         speed                speed
                 by __________.
                 In a diesel electric plant, raising the generator's field   increase in speed decrease in speed affect generator           affect main motor
                 excitation will cause the DC propulsion motor to                                                speed only                 speed if done in
                 __________.                                                                                                                conjunction with
12   7     A                                                                                                                                higher generator
                                                                                                                                            engine speeds



                 Electric coupling excitation is reduced at slow speeds increase speed            increase shaft       prevent coupling     prevent coupling
12   8     C
                 to __________.                                           control                 torque               overheating          slippage
                 A three-phase alternator is operating at 450 volts with 17.8 KW                  23.2 KW              30.6 KW              37.8 KW
                 the switchboard ammeter indicating 300 amps. The kw
                 meter currently indicates 163.6 KW, with a power
12   10    B     factor of 0.7. If the power factor increases to 0.8, the
                 KW meter reading would increase by __________.

                 A semiconductor that decreases in resistance with an        resistor             thermistor           diode                thermopile
12   11    B     increase in temperature is known as a __________.


                                                                                1                                                        Electrical Questions-April 2009
Bk   Num   Ans                         Question                            Answer A                Answer B             Answer C               Answer D         Illustr
                 The shunt used in an ammeter should be connected in series with the          parallel with the    parallel with the      series with the
                 __________.                                          load and in parallel    load and in series   load and in parallel   load and in series
12   12    A
                                                                      with the meter          with the meter       with the meter         with the meter
                                                                      movement                movement             movement               movement
                 Brushless generators are designed to operate without brushes                 slip rings           commutators            all of the above
12   13    D
                 the use of __________.
                 An operating characteristic appearing on the name    type of overload        rated slip           temperature rise       locked rotor torque
12   14    C     plates of shipboard AC motors is __________.         protection

                 Low horsepower, polyphase, induction motors can be      compensator          auto-transformer     across-the-line        primary-resistor
12   15    C     started with full voltage by means of __________.       starters             starters             starters               starters

                 Which of the listed devices may be installed on a large Temperature          A CO2 fire           Electric space     All of the above.
                 turbo-electric alternating current propulsion generator? detector coils      extinguishing        heaters to prevent
                                                                          inserted in the     system.              condensation of
12   16    D                                                              stator slots for                         moisture.
                                                                          measuring stator
                                                                          temperature.

                 Moisture damage, as a result of condensation            installing a light   coating the switch venting the switch using strip heaters
                 occurring inside of the cargo winch master switches,    bulb in the          box internals with box regularly      inside the switch
12   17    D
                 can be reduced by __________.                           pedestal stand       epoxy sealer                          box

                 Which of the following conditions will occur if the     The brake will be    The motor will       The load               Nothing will
                 solenoid coil burns out on a cargo winch with an        set by spring        overspeed and        suspended from         happen; the winch
                 electrical brake?                                       force.               burn up.             the cargo boom         will continue to
12   18    A                                                                                                       will fall.             operate as usual.



                 Which of the listed battery charging circuits is used to Normal charging     Quick charging       Trickle charging       High ampere
                 maintain a wet-cell, lead-acid, storage battery in a fully circuit           circuit              circuit                charging circuit
12   19    C
                 charged state during long periods of disuse?

                 In the event of a power failure during cargo loading  a manual override the weight of the         a spring set brake a hand operated
                 operations, the movement of an electric powered cargo switch            load on the boom                             band brake
12   20    C
                 winch will be stopped by __________.

                 A ground can be defined as an electrical connection     shunt field          circuit breaker      metal framework        interpole
12   21    C     between the wiring of a motor and its __________.




                                                                            2                                                        Electrical Questions-April 2009
Bk   Num   Ans                         Question                           Answer A                  Answer B           Answer C         Answer D                 Illustr
                 External shunts are sometimes used with ammeters to increase meter            permit shunts with prevent damage to reduce reactive
                 __________.                                         sensitivity               larger resistances the meter          power factor error
                                                                                               to be utilized     movement from
12   22    C                                                                                                      heat generated by
                                                                                                                  the internal shunt

                 The output voltage of a 440 volt, 60 hertz, AC           prime mover          strength of the       load on the          number of poles
12   23    B
                 generator is controlled by the __________.               speed                excitation field      alternator
                 Which of the following statements represents the main    Contactors control   A relay is series     Contactors can       Contactors are
                 difference between a relay and a contactor?              current and relays   connected and a       handle heavier       made from silver
12   25    C                                                              control voltage.     contactor is          loads than relays.   and relays are
                                                                                               parallel connected.                        made from copper.

                 Which of the following statements represents an          Provides DC          Used as a voltage Used in photo cell Used to eliminate
                 application of a silicon controlled rectifier?           power for a main     reference diode.  sensor circuits for AC power supply
12   28    A
                                                                          propulsion motor.                      boiler burners.     hum.

                 The electrolyte used in a nickel-cadmium battery is      diluted sulfuric     potassium             lead sulfate         zinc oxide
12   29    B
                 distilled water and __________.                          acid                 hydroxide
                 What damage may occur to the components of a             Overheating of the   Contamination of      Sparking at the      Rapid corrosion of
12   30    D     winch master control switch, if the cover gasket         winch motor.         lube oil.             winch motor          switch
                 becomes deteriorated?                                                                               brushes.             components.
                 An accidental path of low resistance, allowing passage   open circuit         short circuit         polarized ground     ground reference
12   31    B     of abnormal amount of current is known as a/an                                                                           point
                 __________.
                 A resistance in a circuit of unknown value is to be      both meters in       both meters in        the ammeter in       the ammeter in
                 tested using the voltmeter/ammeter method.               series with the      parallel with the     series and the       parallel and the
12   32    C     Therefore, the meters should be connected with           resistance           resistance            voltmeter in         voltmeter in series
                 __________.                                                                                         parallel with the    with the resistance
                                                                                                                     resistance
                 In general, polyphase induction motors can be started    compensator          auto-transformer      across-the-line      primary-resistor
12   34    C     on full line voltage by means of __________.             starters             starters              starters             starters

                 The purpose of a short circuit forcing module (short     high speed           continuity of         isolation of short   all of the above
                 time trip) installed in a branch line is to provide      clearance of low     service on main       circuits by
12   37    D     __________.                                              impedance short      bus under short       selective tripping
                                                                          circuits in the      circuit conditions    of branch circuit
                                                                          branch               in a branch           breakers
                 Which of the symbols shown in the illustration           A                    B                     C                    D
12   38    B                                                                                                                                                    EL-0078
                 represents an NPN type transistor?


                                                                             3                                                       Electrical Questions-April 2009
Bk   Num   Ans                           Question                               Answer A             Answer B             Answer C            Answer D           Illustr
                 You are performing an out-of-circuit test of the semi-    A low reading with   A low reading with   A low reading with   A low reading with
                 conductor shown in the illustration. Using an             red lead on "A"      red lead on "A"      black lead on "A"    black lead on "A"
                 ohmmeter on 'low power' position and with leads           and black lead on    and black lead on    and red lead on      and red lead on
12   40    C     properly installed, which of the listed results would     "C"; and a high      "B"; and a high      "B"; and a high      "C"; and a high       EL-0068
                 indicate a good Collector-Base junction?                  reading with the     reading with the     reading with the     reading with the
                                                                           leads reversed.      leads reversed.      leads reversed.      leads reversed.

                 A direct current passing through a wire coiled around a magnetic shield        electromagnet        piezoelectric        electromagnetic
12   41    B     soft iron core is the description of a simple                                                       device               domain
                 __________.
                 To properly use a hook-on-type volt/ammeter to check de-energize the           hook the jaws of     connect the          short the test
                 current flow, you must FIRST __________.                circuit to allow       the instrument       voltage test leads   leads and calibrate
12   42    B                                                             connection of the      around the           to the appropriate   the instrument to
                                                                         instrument in          insulated            terminals            zero
                                                                         series                 conductor
                 The use of four diodes, in a full-wave bridge rectifier provide                allow a very high  convert direct      offer high
                 circuit, will __________.                               unidirectional         leakage current    current to          opposition to
12   43    A
                                                                         current to the load    from the load      alternating current current in two
                                                                                                                                       directions
                 Autotransformer starters or compensators are              reduce the voltage increase the         provide a backup allow the voltage
                 sometimes used with polyphase induction motors to         applied to the     voltage for 'across- means of voltage to be either
                 __________.                                               motor during the   the-line starting'   regulation for      stepped up or
                                                                           starting period                         emergency           down, depending
12   44    A                                                                                                       starting            on the application,
                                                                                                                                       to ensure full
                                                                                                                                       torque

                 A molded-case breaker provides protection against    shading coil              arc quencher         electromagnet        holding coil
12   47    C
                 short circuits by using a/an __________.
                 The method used to produce electron emission in most photoelectric             secondary electric cold cathodic          thermionic
12   48    D     vacuum tubes is known as __________.                 emission                  emission           electric emission      emission

                 You are performing an out-of-circuit test of the semi-    A low reading with   A high reading       A low reading with   A high reading
                 conductor shown in the illustration. Using an ohmmeter    red lead on "B"      with red lead on     red lead on "A"      with red lead on
                 on 'low power' position and with leads properly           and black lead on    "B" and black lead   and black lead on    "B" and black lead
12   49    B     installed, which of the listed results would you expect   "C"; and a low       on "C"; and a high   "C"; and a high      on "A"; and a low     EL-0068
                 the Emitter-Collector connections of a good               reading with the     reading with the     reading with the     reading with the
                 component?                                                leads reversed.      leads reversed.      leads reversed.      leads reversed.




                                                                              4                                                      Electrical Questions-April 2009
Bk   Num   Ans                         Question                          Answer A                   Answer B              Answer C             Answer D          Illustr
                 When troubleshooting electronic equipment, you     to prevent excess          for AC                whenever a low        so as not to load
                 should use a high impedance multimeter __________. current flow               measurements          impedance meter       down the circuit
                                                                    through the meter          only and a low        is not available,     and obtain
12   50    D                                                        that would                 resistance meter      regardless of the     erroneous voltage
                                                                    damage it                  for DC                components being      readings
                                                                                               measurements          tested

                 Which of the listed devices is used to measure           Transducer           Reducer               Transformer           Rectifier
12   51    A
                 pressure and convert it to an electrical signal?
                 Grounds occurring in electrical machinery as a result of deterioration        excessive heat        extended periods      all of the above
12   52    D     insulation failure may result from __________.           through extended                           of vibration
                                                                          use
                 The amount of voltage induced in the windings of an      the number of        the speed at which the strength of the all of the above
                 AC generator depends on __________.                      conductors in        the magnetic field magnetic field
12   53    D                                                              series per winding   passes across the
                                                                                               winding

                 An AC motor using a rheostat in the motor circuit to    squirrel-cage         regenerative          wound-rotor           synchronous
12   54    C
                 vary the speed is called a __________.                  induction motor       braking motor         induction motor       motor
                 Which of the following precautions should you take      Disconnect the        Disconnect the        Lift the brushes      Lift the brushes
                 when securing propulsion generators and motors for      brush pigtails from   brush pigtails from   from commutator       from commutator
                 an extended period of time?                             their contacts and    their contacts and    collector rings and   collector rings and
                                                                         circulate air         discharge carbon      use the built-in      circulate cool dry
12   56    C                                                             through the units.    dioxide into the      heater to prevent     air through the
                                                                                               units to keep them    moisture              units.
                                                                                               dry.                  accumulation.

                 When reading electrical motor controller diagrams, it   current paths in      current paths in      circuits subject to   circuits subject to
                 helps to know that __________.                          the control circuit   the power circuit     500 volts or          500 volts or
                                                                         are drawn as          are drawn as          greater are drawn     greater are drawn
12   59    B                                                             heavy lines and in    heavy lines and in    as heavy lines and    as light lines and
                                                                         the power circuit     control circuit as    below 500 volts as    below 500 volts as
                                                                         as lighter lines      lighter lines         lighter lines         heavy lines

                 The device that most commonly utilizes the principle of diode                 transformer           transistor            rheostat
12   61    B     electromagnetic induction is the __________.

                 A tubular fuse should always be removed from a fuse     a screwdriver         a pair of insulated any insulated           fuse pullers
12   62    D     panel with __________.                                                        metal pliers        object

                 One factor that determines the frequency of an          number of turns of speed of the rotor strength of the             strength of the
12   63    B     alternator is the __________.                           wire in the                           magnets used                output voltage
                                                                         armature coil

                                                                             5                                                       Electrical Questions-April 2009
Bk   Num   Ans                          Question                              Answer A               Answer B               Answer C             Answer D           Illustr
                 The variable resistance placed in the rotor circuit of a speed control          frequency control     voltage control       use as a split-
12   64    A     wound-rotor induction motor provides for __________.                                                                        phase motor

                 Which of the motors for the devices listed below is       Fan                   Pump                  Winch                 Machine tool
12   65    C
                 fitted with an instantaneous overload relay?
                 In the illustration circuit, A, B, C, and D are each 12   (+) 48 volts          (-) 24 volts          (-) 48 volts          (+) 24 volts
                 volts. What is the voltage at the output lead connected
12   66    B                                                                                                                                                       EL-0039
                 to "A" and "B" with respect to the output lead
                 connected to "C" and "D"?
                 A molded-case circuit breaker provides protection         electromagnet         shading coil          arc quencher          burn away strip
12   67    A
                 against short circuits by using a/an __________.
                 Which of the following statements concerning analog       The variables in      There are no basic    Analog devices        Operations in a
                 and digital devices are correct?                          digital systems are   differences           are superior in       digital device are
                                                                           fixed quantities,     between the two       accuracy              performed
                                                                           and the variables     systems.              compared to           simultaneously.
12   68    A                                                               in analog systems                           digital devices.
                                                                           are continuous
                                                                           quantities.

                 The number of cells in a 12 volt lead-acid battery is     three cells           four cells            six cells             twelve cells
12   69    C
                 __________.
                 In the illustration circuit, A, B, C, and D are each 12   (+) 48 volts          (-) 24 volts          (-) 48 volts          (+) 24 volts
                 volts. What is the voltage of the lead connected to C
12   70    D                                                                                                                                                       EL-0039
                 and D with respect to the lead connected to A and B?

                 The Wheatstone bridge is a precision measuring            inductance            capacitance           resistance            amperage
12   71    C     instrument utilizing the principle of changes in
                 __________.
                 The greatest detrimental effect on idle electrical        loss of residual      absorption of         insulation varnish    dirt collecting on
12   72    B     equipment, such as cargo pump motors, is the              magnetism             moisture in the       flaking               the windings
                 __________.                                                                     insulation
                 The frequency output of an operating alternator is        relative speed of     number of turns of    strength of the       output voltage
12   73    A     controlled by the __________.                             the rotor poles       wire in the           magnets used
                                                                                                 armature coil
                 Which of the following physical characteristics does a    Slip rings            End rings             A centrifugal         End plates
12   74    A     wound-rotor induction motor possess that a squirrel                                                   switch
                 cage motor does not?
                 The current at which a magnetic-type overload relay       reduces magnetic      reduces magnetic      increases             increases
                 tends to trip may be decreased by raising the plunger     pull on the plunger   pull on the plunger   magnetic pull on      magnetic pull on
                 further into the magnetic circuit of the relay. This      and requires more     and requires less     the plunger and       the plunger and
12   75    D     action __________.                                        current to trip the   current to trip the   requires more         requires less
                                                                           relay                 relay                 current to trip the   current to trip the
                                                                                                                       relay                 relay

                                                                              6                                                           Electrical Questions-April 2009
Bk   Num   Ans                             Question                              Answer A               Answer B            Answer C             Answer D            Illustr
                 If the line voltage to the controller shown in the          110 volts              220 volts           440 volts            660 volts
12   76    B     illustration is 440 volts, what voltage is applied across                                                                                          EL-0080
                 the motor when contacts "S" close?
                 Which of the listed logic gates is considered to be a       NAND                   OR                  NOR                  All of the above.
12   78    B     BASIC building block (basic logic gate) used in logic
                 diagrams?
                 When choosing a battery for a particular application,       amp-hour capacity terminal polarity        stability under      ambient
12   79    A     major consideration should be given to the battery's                                                   charge               temperature rise
                 __________.
                 What operational characteristics do the components          Standard and       Stop and Restart        Subnormal and        Start and Run
                 labeled as "S" and "R" represent in the motor controller    Reverse directions features                Regular loading      functions
12   80    D                                                                                                                                                        EL-0080
                 diagram shown in the illustration?

                 The rated temperature rise of an electric motor is the      average            normal                  average              permissible
                 __________.                                                 temperature at any temperature rise        temperature rise     difference in the
                                                                             given latitude     above the               due to resistance    ambient
12   81    B                                                                                    standard ambient        at 10% overload      temperature of the
                                                                                                temperature at                               motor due to
                                                                                                rated load                                   existing weather
                                                                                                                                             conditions
                 Regarding an AC generator connected to the main             governor speed         voltage regulator   balance coil         phase-balance
                 electrical bus; as the electric load and power factor       droop setting                                                   relay
                 vary, a corresponding change is reflected in the
12   83    B     generator armature reaction. These changes in
                 armature reaction are compensated for by the
                 __________.
                 An electrical device which prevents an action from          limit                  monitor             modulator            interlock
12   85    D     occurring until all other required conditions are met is
                 called a/an __________.
                 The diagram shown in the illustration represents a          dual speed, 2-         navigation running uninterruptible       common
12   86    B     __________.                                                 winding motor          light circuit      power supply          fluorescent lighting   EL-0058
                                                                             controller                                circuit               circuit
                 A circuit breaker and a fuse have a basic similarity in     can be reset to        should open the    will burn out when    all of the above
                 that they both __________.                                  energize the circuit   circuit when       an over current
12   87    B
                                                                                                    overloaded         flow develops

                 Which two components, shown in the illustration,          "G" and "H"      "E" and "I"                 "F" and "H"          "E" and "G"
12   88    B     acting together will disconnect the motor from the line                                                                                            EL-0080
                 in case of a sustained motor overload?
                 The electrolyte in a lead-acid storage battery consists hydrogen chloride calcium chloride             sulfuric acid        muriatic acid
12   89    C
                 of distilled water and __________.
                 The torque produced by a motor when its shaft will not locked-rotor torque pullout torque              breakdown torque torque margin
12   91    A     turn, even though rated voltage is applied to the stator,
                 is known as __________.
                                                                                 7                                                        Electrical Questions-April 2009
Bk   Num   Ans                           Question                                    Answer A             Answer B             Answer C             Answer D            Illustr
                 Electrical leads and insulation on a motor should be           heat-resisting       heat-resisting        insulating varnish  insulating white
12   92    C
                 painted with __________.                                       acrylic              aluminum                                  lead
                 A degree of control over the speed of a slip ring              adjusting governor   changing the          inserting           inserting
                 induction motor can be obtained by __________.                 linkage              number of phases      resistance into the resistance into the
12   94    D
                                                                                                     to the motor          stator circuit      rotor circuit

                 As shown in the illustration, what happens when "A" is         "H" energizes and    "F" goes out          "G" sounds an         "C" opens causing
12   95    C     closed, "B" is in position "2" and component 'E2' burns        "D" makes            allowing "G" to       alarm and "F"         "A" to also open.     EL-0058
                 out?                                                           contact.             disconnect.           illuminates.
                 A circuit breaker differs from a fuse in that a circuit        melts and must be    is enclosed in a      gives no visual       trips to break the
                 breaker __________.                                            replaced             tube of insulating    indication of         circuit and may be
                                                                                                     material with metal   having opened the     reset
12   97    D                                                                                         ferrules at each      circuit
                                                                                                     end

                 During start-up of the circuit shown in the illustration, it   component "D" is     the power             component "A" is      component "B"
                 is noted that the ends of component "C" alternately            loose and due to     system's voltage is   shorted and           contacts are
                 glow and become dark without the tube illuminating.            the ship's           fluctuating in and    therefore unable to   opening and
12   99    C     The most probable cause for this is that __________.           vibrations makes     out of the range      produce the high      closing thus          EL-0081
                                                                                and breaks           necessary for         voltage required to   prohibiting
                                                                                contact              proper operation      start the lamp        sufficient current
                                                                                                                                                 flow
                 Incandescent lamps are classified according to                 shape of bulb and size and style of        operating voltage     all of the above
12   100   D     __________.                                                    type of service   base                     and wattage

                 As a general rule, the first troubleshooting action to be      draw a one line      test all fuses and    take megger           insulate the
12   102   B     taken in checking faulty electric control devices is to        diagram of the       measure the line      readings              apparatus from
                 __________.                                                    circuitry            voltage                                     ground
                 An electrical device which employs a stationary                magnetic amplifier   ship's service        three-wire DC         saturable core
12   103   B     armature and a rotating electromagnetic field is                                    alternator            generator             reactor
                 commonly used aboard ship as a __________.
                 The main purpose of the auxiliary winding on a split-          limit the starting   increase the          start the motor       keep the motor
                 phase, single-phase motor is to __________.                    voltage              starting current                            running in the
12   104   C                                                                                                                                     event the main
                                                                                                                                                 winding should fail

                 As shown in the illustration, the same indication occurs 'E2' burns out             'H2' opens            "G" opens             "F" burns out
12   105   A                                                                                                                                                           EL-0058
                 when "C" opens as when __________.
                 The device shown in the illustration is a/an             noise filtering            auto transformer      fluorescent light     power factor
12   106   B     __________.                                              choke                                            ballast               correction inductor   EL-0083



                                                                                   8                                                         Electrical Questions-April 2009
Bk   Num   Ans                            Question                                Answer A              Answer B             Answer C              Answer D            Illustr
                 The turns ratio of device "A" shown in the illustration is   110 volts             220 volts            440 volts             1760 volts
                 four to one and all taps are equally spaced. If 440 volts
12   107   A                                                                                                                                                          EL-0082
                 were applied between 'H1' and 'H4', what would appear
                 across 'X1' and 'X4'?
                 Which of the following statements describes the              Ambient               Increased ambient    Ambient               A reduced ambient
                 significance of ambient temperature in relation to the       temperature           temperature          temperature is not    temperature
                 service life of electronic components?                       should be as high     decreases the        significant as long   causes a
12   108   B                                                                  as possible to        service life of      as the relative       corresponding
                                                                              drive off moisture.   electronic           humidity is kept      reduced service
                                                                                                    components.          low.                  life.

                 The state of charge of a lead acid storage battery is  testing of the              ampere hour          specific gravity of   total cell voltages
12   109   C     best indicated by the __________.                      individual cell             capacity of the      the electrolyte
                                                                        voltages                    battery
                 What is indicated by gradual blackening at the ends of The unit is in              The tube is          The circuit voltage The circuit current
12   110   B     component "C" shown in the illustration?               danger of                   nearing the end of   is too high.        is too high.             EL-0081
                                                                        exploding.                  its useful life.
                 Which of the following statements is correct           The ringing circuit         The common           The ringing circuit   The talking and
                 concerning the circuits in a sound powered telephone is composed of                talking circuit is   has two grounded      calling circuits are
                 system?                                                only one common             composed of two      wires connected to    electrically
12   111   B                                                            wire to ground.             ungrounded wires.    each station.         dependent upon         EL-0093
                                                                                                                                               each other.

                 The first requirement for logical troubleshooting of any collect all available recognize normal        identify the           isolate the faulty
12   112   B     system is the ability to __________.                     data on a casualty operation                  probable cause of      component
                                                                                                                        a symptom
                 The load sharing characteristics of two diesel               load limit settings   idle speed settings speed limit            speed droop
12   113   D     generators operating in parallel are mostly dependent                                                  settings               settings
                 on their governor __________.
12   114   C     What type of rotor is used in split-phase motors?            Drum                  Salient pole         Squirrel-cage         Wound-rotor
                 Which device will stop the motor shown in the                "F"                   "G"                  "H"                   "I"
12   115   A     illustration in case of a short-circuit (high current)                                                                                               EL-0080
                 motor overload?
                 As shown in the illustration, what maintenance would     Change out both Clean the glass       File the points at             Take megger
                 be required of the circuit components?                   "C" units monthly. surrounding 'E1' & the upper end of               readings on 'E1' &
12   116   B                                                                                                                                                          EL-0058
                                                                                             'E2' as needed.    "G" every six                  'E2' windings
                                                                                                                months.                        quarterly.
                 Which component of the circuit shown in the illustration A                  B                  C                              D
12   117   C                                                                                                                                                          EL-0081
                 is the lamp?



                                                                                 9                                                        Electrical Questions-April 2009
Bk   Num   Ans                           Question                              Answer A            Answer B                 Answer C            Answer D          Illustr
                 Tightly knit metal braid wire can be used with a printed conductor           required to               electrically       reactance in the
                 circuit board when __________.                           resistance is not a desolder                  produced           circuit must be
                                                                          factor              components on             magnetic fluxes    kept to a minimum
12   118   B                                                                                  the board                 would cause
                                                                                                                        inaccuracies in
                                                                                                                        adjacent
                                                                                                                        components
                 If the line voltage to the controller shown in the           110 volts            220 volts            440 volts          660 volts
12   120   C     illustration is 440 volts, what is applied across the                                                                                           EL-0080
                 control circuit?
                 AC circuits possess characteristics of resistance,           ohms                 mhos                 henrys             farads
                 inductance, and capacitance. The capacitive
12   121   A
                 reactance of a circuit is expressed in __________.

                 In an AC generator, direct current from a separate           by means of slip  by means of a         by means of          to minimize the
12   123   A     source is passed through the windings of the rotor           rings and brushes commutator            rotating bar         danger of arc over
                 __________.                                                                                          magnet
                 The purpose of a cage rotor winding placed on the            provide excitation   start the machine contribute extra      prevent the
                 rotor of a synchronous motor is to __________.               to the DC field      as an induction    torque at            machine from
12   124   B
                                                                                                   motor              synchronous          falling out of step
                                                                                                                      speed
                 Motor controllers are seldom troubled with grounds           the auxiliary        the contactors and the resistor banks   there are separate
                 because __________.                                          contacts have a      relays are         are composed of      switches for the
12   125   B                                                                  high resistance      mounted on a non- individual series-    motor and the
                                                                              connection           conducting panel connected units        control

                 Which component of the circuit shown in the illustration     A                    B                    C                  D
12   128   B                                                                                                                                                     EL-0081
                 is the starter?
                 The turns ratio of device "A" shown in the illustration is   30 volts             120 volts            480 volts          1440 volts
                 a step down four to one and all the taps are equally
12   129   D     spaced. If 120 volts was indicated on the secondary                                                                                             EL-0082
                 between 'X1' and 'X2', what would be indicated across
                 'H1' and 'H4'?
                 The turns ratio of device "A" shown in the illustration is   15 volts             30 volts             480 volts          960 volts
                 four to one and all taps are evenly spaced. If 120 volts
12   130   A                                                                                                                                                     EL-0082
                 were applied to terminals 'H1' and 'H3', what would
                 appear at 'X1' and 'X2'?
                 The electrical energy necessary to transmit a person's       dry cell batteries   the ship's service   the emergency      the speaker's
12   131   D     voice over a sound-powered telephone circuit is                                   switchboard          switchboard        voice
                 obtained from __________.
                 Which of the listed procedures should be carried out to      Fill the motor      Strap silica gel      Place heat lamps   Cover the
                 prevent moisture damage to electrical apparatus              housing with CO2 around the               in the motor       equipment with a
12   132   C
                 during extended periods of idleness?                         to inert the space. commutator.           housings.          canvas tarpaulin.

                                                                                  10                                                    Electrical Questions-April 2009
Bk   Num   Ans                          Question                               Answer A            Answer B            Answer C            Answer D          Illustr
                 A constant output voltage from an AC generator is         prime mover        exciter generator   voltage regulator   reverse power
12   133   C
                 maintained by the __________.                             governor                                                   relay
                 Amortisseur windings are installed in a synchronous       reduce eddy        produce a higher    provide a means     eliminate arcing
                 motor to __________.                                      current losses     power factor        for starting        between the stator
12   134   C
                                                                                                                                      and the rotor

                 Electric strip heaters are used in motor controllers to   prevent freezing of keep the           prevent             minimize
                 __________.                                               movable contacts components at         condensation of     resistance in
12   135   C                                                                                   their design       moisture            internal circuits
                                                                                               ambient
                                                                                               temperature
                 The purpose of the capacitor within component "B" of      prolong the life of discharge the  counteract the          store power to
                 the circuit shown in the illustration is to __________.   the component's     neon within theinductive               operate the circuit
12   136   A                                                                                                                                                EL-0081
                                                                           contacts            envelope       reactance in the        should "D" open
                                                                                                              circuit
                 A fuse that blows often should be replaced only with a    the recommended higher current and higher current and      lower current and
                 fuse of __________.                                       current and     voltage rating     lower voltage           higher voltage
12   137   A
                                                                           voltage rating                     rating                  rating

                 Which of the listed conditions is an advantage of a PN Longer life.         No warm up time. Less delicate.       All of the above.
12   138   D
                 diode over a vacuum diode?
                 The freezing point of the electrolyte in a fully charged higher than in a   lower than in a    the same as in a higher than in a
                 lead-acid battery will be __________.                    discharged battery discharged battery discharged battery discharged
12   139   B                                                                                                                       battery, but the
                                                                                                                                   specific gravity will
                                                                                                                                   be less
                 A load is connected to the secondary of the device       1 amp              10 amps            100 amps           1000 amps
                 illustrated and the current through the load is 10 amps.
12   140   C     If the step-up ratio is 10 to 1 and the input voltage is                                                                                   EL-0055
                 110 VAC, what will be the current flow through the
                 primary?
                 The heating of conductors as a result of resistance in a line droop         line loss          IR drop            hysteresis
12   141   B     distribution circuit causes a power loss expressed as
                 __________.
                 To repair a small electrical motor that has been         wash it with fresh renew the          send it ashore to rinse all electrical
                 submerged in saltwater, you should __________.           water and apply an windings           an approved        parts with a
                                                                          external source of                    service facility   carbon
                                                                          heat                                                     tetrachloride
12   142   A                                                                                                                       cleaning solvent
                                                                                                                                   and then blow dry
                                                                                                                                   the motor with
                                                                                                                                   compressed air


                                                                             11                                                  Electrical Questions-April 2009
Bk   Num   Ans                          Question                                 Answer A            Answer B           Answer C               Answer D          Illustr
                 The output voltage of a three-phase alternator is          AC voltage to the AC voltage to the     DC voltage to the    DC voltage to the
12   143   D
                 regulated by the __________.                               armature           field                armature             field
                 The function of damper windings in a synchronous           eliminate slippage provide excitation   provide starting     increase efficiency
12   144   C
                 motor is to __________.                                                                            torque
                 A shading coil used in an AC magnetic controller,          reduce vibration   prevent flux         eliminate arcing     energize the
                 functions to __________.                                   and noise in the   buildup in the       when the contacts    operating coil and
12   145   A
                                                                            contactor          operating coil       close                'pull in' the
                                                                                                                                         contacts
                 Which of the listed figures shown in the illustration      A                  B                    C                    D
12   146   B     represents devices connected in a three-phase wye-                                                                                             EL-0084
                 wye arrangement?
                 In a cartridge-type fuse, the metal element is contained   porcelain window   thermal cut out      fiber tube           flasher device
12   147   C
                 in a __________.
                 The illustrated lead acid battery is about to be placed    sponge lead (Pb)   lead peroxide        lead sulfate         a depolarizing mix
12   148   B     in service. The positive plate labeled "D" is made                            (PbO2)               (PbSO4)                                     EL-0031
                 of_______.
                 The illustrated lead acid battery is about to be placed    sponge lead (Pb)   lead peroxide        lead sulfate         zinc oxide (ZnO2)
12   149   A     in service. The negative plate, labeled "E", is made                          (PbO2)               (PbSO4)                                     EL-0031
                 of_______.
                 When maintaining the circuit shown in the illustration,    Glass fragments    The contained        The inside coating All of the above.
                 what dangers are associated with component "C"             may cut a person's mercury vapor is     of phosphor is
12   150   D     should it become broken?                                   skin.              highly toxic.        highly poisonous.                           EL-0081


                 In process control terminology, continuously variable binary values           digital values       bumpless values      analog values
                 values which change without distinct increments, such
12   151   D
                 as temperature, pressure, or level are called
                 __________.
                 The proper way to apply plastic electrical tape to an apply tape to the     wind the tape so       apply the tape in    heat the tape with
                 electric cable splice is to __________.               braided cover, but    that each turn         one non-             a soldering iron for
12   152   B
                                                                       avoid touching it     overlaps the turn      overlapping layer    good bonding
                                                                                             before it              only
                 Which of the following statements is true concerning all Each has three     Each has one           All three-phase      The three phases
                 three-phase alternators?                                 separate but       armature winding       alternators are      always provide
                                                                          identical armature acted on by three      designed to          power to the load
                                                                          windings acted on identical but           operate with a 0.8   through three sets
12   153   A                                                              by one system of separate systems         leading power        of slip rings and
                                                                          rotating magnets. of rotating             factor.              brushes.
                                                                                             magnets.




                                                                                12                                                 Electrical Questions-April 2009
Bk   Num   Ans                             Question                            Answer A              Answer B             Answer C              Answer D       Illustr
                 In the illustration, the component labeled "G" is        hard rubber,           porous inside to     pre-charged for (-) All the above
                 __________.                                              plastic or             absorb excess        and (+) in
12   154   A                                                                                                                                                  EL-0031
                                                                          bituminous             positive ions        manufacturing
                                                                          composition
                 The device shown in the illustration is being used       in a step-down         in a step-up         in an isolation   as a filter
12   156   A                                                                                                                                                  EL-0083
                 __________.                                              operation              operation            circuit
                 Time delayed or delayed action-type fuses are            prevent grounds in     prevent opens in     permit momentary guard lighting and
                 designed to __________.                                  branch circuits        motor circuits       overloads without electronic circuits
12   157   C
                                                                                                                      melting

                 Silicon diodes which are designed for a specific       tunnel diodes            hot-carrier diodes   compensating         Zener diodes
                 reverse breakdown voltage, and are most often used in                                                diodes
12   158   D
                 electronic power supply voltage regulators, are called
                 __________.
                 The symbol in figure "A" shown in the illustration     diac                     field effect         silicon controlled   uni-junction
12   159   D                                                                                                                                                  EL-0065
                 represents a __________.                                                        transistor           rectifier            transistor
                 If the inputs to the diagram shown in the illustration 0,0                      0,1                  1,0                  1,1
                 were J=1, K=0, H=1, L=1, M=0, what logic levels
12   160   A                                                                                                                                                  EL-0089
                 would be indicated at points "X" and "Y" respectively?

                 Which of the following statements best describes the     Felted asbestos        Cotton cloth        Rubber insulation Paper
                 material known as varnished cambric?                     sealed with            coated with         coated with a layer impregnated with
                                                                          varnish.               insulating varnish. of tin.             mineral oil,
                                                                                                                                         specially wrapped
12   161   B                                                                                                                             with nonmetallic
                                                                                                                                         tape, and coated
                                                                                                                                         with varnish.

                 Which component of the circuit shown in the illustration A                      B                    C                    D
12   162   A                                                                                                                                                  EL-0081
                 is the ballast?
                 A synchronous motor maintains synchronism with the field strength               DC current applied   the stator poles    the stator flux
                 rotating field because __________.                       varies directly with   to the rotor coils   are dragged         rotates in the
                                                                          rotor slip             causes the rotor     around due to the opposite direction
                                                                                                 magnets to lock in   flux created by the
12   164   B                                                                                     with the rotating    excitation current
                                                                                                 flux of the stator



                 What is the maximum allowable primary current of a 2 1.1 amps                   4.5 amps             18.1 amps            27.7 amps
                 KVA step-down transformer with a four to one turns
12   165   B
                 ratio if the primary is connected across a 440 volt line?


                                                                             13                                                       Electrical Questions-April 2009
Bk   Num   Ans                             Question                              Answer A              Answer B            Answer C            Answer D            Illustr
                 What is represented by the solid dots within               The fact that these   An indication that   The particular     All of the above.
                 components "B" and "C" of the diagram shown in the         parts are subject     they are for 110     components
12   166   C     illustration? (See illustration EL-0081)                   to wear and           volt AC operation    contain a gas such                         EL-0081
                                                                            replacement.          only.                as neon or argon.

                 The part of a fuse that melts and opens an electrical      copper and            steel and babbitt  aluminum or            zinc or an alloy of
12   167   D
                 circuit is typically made of __________.                   antimony                                 beryllium alloy        tin and lead
                 The leads of the device in figure "A" shown in the         source, gate and      emitter, base and emitter, base 1         anode, cathode
12   168   C                                                                                                                                                      EL-0065
                 illustration are named the __________.                     drain                 collector          and base 2             and gate
                 If 450 volts AC were measured across the load as           open winding          properly operating open winding           ground on one
12   170   C     shown in the illustration it would indicate a/an           between 'H1' and      circuit            between 'X1' and       side of 'Ep'          EL-0083
                 __________.                                                'X1'                                     'X4'
                 The cross-sectional area of shipboard electrical cable     millimeters           gage numbers       centimeters            circular mils
12   171   D
                 is expressed in __________.
                 To effectively clean a commutator in good physical         trichloride ethylene kerosene              a canvas wiper       a commutator
12   172   C
                 condition, you should use __________.                                                                                      stone
                 What will be the phase angle relationship of a six-pole,   60°                   120°                 180°                 360°
12   173   B
                 three-phase, rotating field generator?
                 The function of amortisseur, or damper windings in a       eliminate slippage provide excitation    provide starting       increase efficiency
12   174   C
                 synchronous motor is to __________.                                                                 torque
                 The main difference between a motor control circuit        a magnetic            normally open line thermal-overload       a momentary-
                 containing low voltage release and low voltage             operating coil        contacts           protection             contact start
12   175   D
                 protection is that the latter contains __________.                                                                         button

                 Figure "A" of the diagram shown in the illustration has 64 volts                 110 volts            190 volts            762 volts
                 a turns ratio of four to one. If a three-phase 440 volt
12   176   B     supply is connected to terminals "A-B-C", what voltage                                                                                           EL-0084
                 should develop across terminals "a-b-c"?

                 Fuses placed in series with a thermal trip-type circuit    time-delay            short-circuit        short duration       sustained overload
12   177   B     breaker are used for __________.                           protection            protection           surge protection     protection

                 When charging lead-acid batteries, you should reduce prevent excessive allow equalization reduce lead                      increase lead
                 the charging rate as the battery nears its full charge gassing and     of cell voltages   sulfate deposits                 peroxide formation
12   179   A
                 capacity to __________.                                overheating

                 Figure "D" shown in the illustration represents a     silicon controlled         light emitting diode photo sensitive      Zener diode
12   180   B                                                                                                                                                      EL-0067
                 __________.                                           rectifier                                       diode
                 Ammeters and voltmeters used in sinusoidal AC power Peak value                   Root-mean-square Average value            Maximum value
12   181   B     systems indicate which of the following values of the                            value
                 waveforms measured?


                                                                              14                                                         Electrical Questions-April 2009
Bk   Num   Ans                        Question                                   Answer A              Answer B            Answer C              Answer D             Illustr
                 Before reassembling any machinery, you should              replace all           apply a heavy coat clean any               coat all parts with
                 __________.                                                bearings              of oil to all mating corroded surfaces     alemite grease
12   182   C
                                                                            regardless of         surfaces             and file all burrs
                                                                            length of service                          smooth
                 The purpose of the commutator and brushes on a DC          transfer generated    convert the          provide a sliding     reduce sparking
                 generator is to __________.                                direct current        alternating voltage contact method to      between the
                                                                            voltage from the      generated within excite the field          armature and the
12   183   B                                                                armature to the       the armature to a                          carbon brushes
                                                                            line                  direct voltage

                 A common source of field excitation for synchronous        low voltage battery motor attenuator        DC rectifier         AC supply
12   184   C
                 motors is a/an __________.                                                     set
                 The type of feature afforded auxiliaries vital to the      low voltage         high amperage           low voltage          high amperage
                 operation of propelling equipment, where automatic         protection          protection              release              release
12   185   C
                 restart after a voltage failure would not create a
                 hazard, is termed __________.
                 During the start-up of the circuit shown in the            component "A" is      component "D" is      component "C" is component "B"
                 illustration, it is noted that the ends of component "C"   open                  closed                the wrong wattage contacts are stuck
12   186   D     remain lighted but the tube does not illuminate. The                                                                     closed                     EL-0081
                 cause of this problem is __________.

                 Which of the following statements correctly applies to     LED and LCD are       The three             The emitter         The collector
                 transistors?                                               the two basic         terminals are         separates the       separates the
12   188   B                                                                types of              called the emitter,   base and collector. emitter and base.
                                                                            transistors.          base, and
                                                                                                  collector.
                 The turns ratio of device "A" shown in the illustration is 37.5 volts            55 volts              220 volts            440 volts
                 four to one and all taps are evenly spaced. If 110 volts
12   189   C     were applied to terminals 'X1' and 'X3', what would be                                                                                              EL-0082
                 indicated across 'H1' and 'H2'?

                 Figure "A" of the diagram shown in the illustration        silicon controlled    IG or MOS field       triac thyristor      junction field effect
12   190   B                                                                                                                                                         EL-0078
                 represents a/an __________.                                rectifier             effect transistor                          transistor
                 The basic measuring unit of inductance is the              coulomb               ohm                   farad                henry
12   191   D
                 __________.
                 Which of the listed precautions should be taken when       Open the machine      Be certain that the Be certain that the All of the above.
                 cleaning the internals of a motor with compressed air?     on both ends so       circuit breaker is  air is clean and as
                                                                            as to allow the air   opened and          dry as possible.
12   192   D                                                                and dust to           tagged on the
                                                                            escape.               feeder panel.

                 The purpose of DC generator brushes is to                  neutralize        conduct electric          convert DC current provide excitation
12   193   B     __________.                                                armature reaction current to an             to AC current      to a DC generator
                                                                                              outside circuit
                                                                              15                                                          Electrical Questions-April 2009
Bk   Num   Ans                         Question                                Answer A                Answer B          Answer C              Answer D            Illustr
                 The most common source of excitation for the rotor of     step-up                half-wave rectifier DC supply            AC supply
12   194   C     a synchronous motor is a/an __________.                   transformer

                 Which of the listed figures shown in the illustration  A                         B                   C                    D
12   195   D     represents devices connected in a three-phase wye-                                                                                               EL-0084
                 delta arrangement?
                 If the inputs to the diagram shown in the illustration 0,0                       0,1                 1,0                  1,1
                 were J=0, K=0, H=1, L=0, M=1, what logic levels would
12   196   C                                                                                                                                                      EL-0089
                 be indicated at points "X" and "Y" respectively?

                 Fuses are rated in __________.                            voltage                amperage       interrupting              all the above
12   197   D
                                                                                                                 capacity
                 Which of the following statements concerning Nickel-      When mixing the When mixing the Nickel-Cadmium                  The electrolyte of
                 Cadmium batteries is true?                                electrolyte always electrolyte always batteries can be          an idle Nickel-
                                                                           add acid to the    add water to the   stored for a long         Cadmium battery
                                                                           water.             acid.              period of time            must be replaced
12   199   C                                                                                                     while still keeping       monthly to
                                                                                                                 a full charge.            maintain battery
                                                                                                                                           condition.

                 What is represented by the two parallel lines within      A ground               An iron core        Ventilation          A mounting base
12   200   B     component "A" of the circuit shown in the illustration?   connection                                 openings                                    EL-0081

12   201   D     Power transformers are rated in __________.               kilowatts-amps         ampere-turns        kilowatt-volts       kilovolt amperes
                 Which of the listed precautions should be observed        Slow the motor         Disconnect the      Secure all           Preheat the
                 before spraying liquid solvent on the insulation of an    down to low            motor from the      ventilation in the   insulation to assist
12   202   B
                 electric motor?                                           speed.                 power source.       area.                in cleaning.

                 The simplest method of controlling the terminal voltage hand-operated            separate exciter in carbon pile         balance coil
                 of compound-wound DC generator is with a                   field rheostat        a series with the   regulator in series diverting neutral
12   203   A     __________.                                                connected in          shunt field         with the load       current through
                                                                            series with the                                               the shunt field
                                                                            shunt field circuit
                 A damper winding is designed as part of a                  increase efficiency   provide starting    provide excitation   eliminate slippage
12   204   B
                 synchronous motor to __________.                                                 torque
                 The type of motor control circuit that will not permit     low voltage           low voltage         overload lockout     reduced voltage
12   205   A     automatic restarting after power is restored, following a protection             release                                  restart
                 power failure, is called __________.
                 The turns ratio of device "B" shown in the illustration is 55 volts              110 volts           220 volts            880 volts
                 two to one (total). If 440 volts were applied to
12   206   B                                                                                                                                                      EL-0082
                 terminals 'H1' and 'H2', what would be indicated across
                 'X1,3' and 'X2,4'?
                 What is the load voltage 'Es' as shown in the              292 volts             360 volts           450 volts            810 volts
12   207   B                                                                                                                                                      EL-0083
                 illustration?
                                                                              16                                                       Electrical Questions-April 2009
Bk   Num   Ans                            Question                                 Answer A            Answer B            Answer C              Answer D         Illustr
                 As shown in the illustration, which of the drawings        A                    B                   C                     D
12   208   B                                                                                                                                                     EL-0076
                 depicts a typical transistor?
                 Local action in a nickel-cadmium battery is offset by      separating the       separating the      adding a small        trickle charging
                 __________.                                                positive and         positive and        amount of lithium
                                                                            negative plates      negative plates     hydroxide to the
12   209   D                                                                with plastic         with resin          electrolyte
                                                                            spacers              impregnated
                                                                                                 spacers
                 Which component will stop the motor shown in the            "E"                 "G"                 "H"                   "I"
12   210   B     illustration in case of an overload in the control circuit?                                                                                     EL-0080

                 Alternating current circuits develop resistance,           ohms                 mhos                henrys                farads
12   211   C     inductance and capacitance. The inductance of a coil
                 is expressed in __________.
                 An insulation resistance test is performed on a            The maximum          The temperature The normal                The complete
                 particular piece of electric equipment. In addition to     allowable            of the machine at temperature rise of     nameplate data
                 the resistance reading, what information listed below      operating            the time the       the machine.           from the
12   212   B     should be entered in the electrical log?                   temperature of the   resistance reading                        resistance test
                                                                            machine.             was taken.                                instrument used to
                                                                                                                                           obtain the reading.

                 A compound generator has a no-load voltage of 250          flat compounded      over compounded under                     terminal
12   213   C     volts and a full-load voltage of 230 volts, and therefore,                                      compounded                compounded
                 is considered to be __________.
                 Which of the following types of motors can be used for Polyphase                Wound-rotor         Induction             Synchronous
12   214   D     correcting power factor during normal operation?

                 When changing out component "B" of the circuit shown it is polarity             there is a danger   component "D"         it must match the
                 in the illustration, it is important to know that    sensitive and must         of phosphor         must be closed        circuit voltage and
                 __________.                                          be inserted as             poisoning should    during the            component "C"
12   216   D                                                          indicated on its           "B'"s bulb break    replacement to        wattage               EL-0081
                                                                      base                                           provide the
                                                                                                                     capacitor's initial
                                                                                                                     charge
                 The reason some electric cables are formed of              increase the         increase their      decrease the          assure good
                 stranded wire is to __________.                            current carrying     flexibility         weight for a given    conductivity at
12   217   B
                                                                            capability for a                         size wire             junction points
                                                                            given size wire
                 A device which prints out a permanent record of the        analogger            bell logger         alarm logger          data logger
12   218   D     plant operating conditions is known as the
                 __________.


                                                                                17                                                    Electrical Questions-April 2009
Bk   Num   Ans                           Question                            Answer A               Answer B           Answer C              Answer D           Illustr
                 Figure "B" of the diagram shown in the illustration has 64 volts               110 volts          190 volts             762 volts
                 a step-down turns ratio of four to one. If a three-phase
12   220   B     440 volt supply is connected to terminals 'A-B-C', what                                                                                       EL-0084
                 voltage should develop across terminals 'a-b-c'?

                 Alternating current circuits develop resistance,            ohms               mhos               henrys                farads
                 inductance, and capacitance. The capacitance of
12   221   D
                 individual capacitors is expressed in __________.

                 The purpose of amortisseur windings in a synchronous reduce eddy               produce a higher   provide a means       eliminate arcing
                 motor is to __________.                              current losses            power factor       for starting          between the stator
12   224   C
                                                                                                                                         and the rotor

                 Since the characteristics of the device shown in figure     oscillators and    class A and B      generator rectifier all of the above
                 "A" of the illustration includes a stable voltage and low   SCR trigger        amplifiers         and filtering
12   226   A                                                                                                                                                   EL-0065
                 current while operating, it can be suitably used in         circuits                              supplies
                 __________.
                 Which solid AWG wire size has the smallest physical         12                 14                 16                    18
12   227   D
                 cross-sectional area?
                 A lead-acid battery is considered fully charged when        electrolyte gasses battery charger    terminal voltage      specific gravity of
                 the __________.                                             freely             ammeter indicates reaches a              all cells reaches
                                                                                                a positive reading constant value at a   the correct value
12   229   D                                                                                                       given temperature     and no longer
                                                                                                                                         increases over a
                                                                                                                                         period of 1 to 4
                                                                                                                                         hours
                 Which of the listed figures shown in the illustration       A                  B                  C                     D
12   230   C     represents devices connected in a three-phase delta-                                                                                          EL-0084
                 wye arrangement?
                 The opposition to the establishment of magnetic lines       resistance         reluctance         impedance             inductance
12   231   B     of force in a magnetic circuit is called the circuit's
                 __________.
                 The insulation resistance of electric equipment and         immediately after every time the      immediately after     every 30 days
                 machinery should be tested for the lowest normal            shutting down the brush rigging is    starting up the       whether the
12   232   A
                 insulation values __________.                               machine           adjusted            machine               machine is in use
                                                                                                                                         or not
                 Which of the terms listed best describes a compound- Flat compounded           Over compounded Under                    Terminal
12   233   C     wound DC generator having a higher voltage at no                                               compounded               compounded
                 load than at full load?
                 The turns ratio of device "B" shown in the illustration is 55 volts            110 volts          440 volts             880 volts
                 two to one (total). If 220 volts were applied to
12   234   A                                                                                                                                                   EL-0082
                 terminals 'H1' and 'H2', what would be indicated across
                 'X3' and 'X4'?

                                                                                  18                                              Electrical Questions-April 2009
Bk   Num   Ans                         Question                                 Answer A               Answer B            Answer C            Answer D           Illustr
                 The purpose of squirrel-cage windings in a                 provide more           produce a higher    eliminate arcing   provide a means
                 synchronous motor is to __________.                        precise balancing      power factor        between the stator for starting
12   236   D
                                                                                                                       and the frame

                 If the inputs to the diagram shown in the illustration 0,0                        0,1                 1,0                  1,1
                 were J=1, K=1, H=0, L=1, M=1, what logic levels would
12   237   D                                                                                                                                                     EL-0089
                 be indicated at points "X" and "Y" respectively?

                 Local action in a dry-cell, or lead-acid storage battery   hydrogen gas is        the electrolyte     potassium            the battery
                 is the process whereby __________.                         liberated              compensates for     hydroxide absorbs    becomes
                                                                                                   overcharging        carbon dioxide       discharged without
12   239   D                                                                                                           from the air         being connected
                                                                                                                                            to a load

                 An important characteristic of the device shown in         higher                 higher power        very high input      all of the above
                 figure "B" of the illustration as compared with            temperature            ratings             resistance
12   240   C                                                                                                                                                     EL-0065
                 conventional NPN or PNP transistors is its                 sensitivity
                 __________.
                 The RMS value of a sine-wave current may also be           average value          maximum value       effective value      instantaneous
12   241   C
                 expressed as the __________.                                                                                               value
                 On tank vessels with an electrically-driven capstan, the   insulation             eddy currents       capacitance          armature
12   242   A     motor should be meggered periodically to test              resistance                                                      reactance
                 __________.
                 A triac thyristor functions as a control device and        two NPN                a diode in series   a bidirectional      a triode tube with
                 basically functions as __________.                         transistors in         with a temperature SCR with a            an extra heavy
12   243   C                                                                parallel with a        sensitive capacitor common gate          grid element
                                                                            common base
                                                                            lead
                 The speed of a squirrel cage induction motor is            diameter of the        number of stator    rotor winding        bar resistance of
12   244   B     determined by the __________.                              stator                 poles               resistance           the conducting
                                                                                                                                            rotor
                 What is the maximum current allowed to be drawn            1.1 amps               4.5 amps            18.1 amps            22.7 amps
                 from the secondary of a 2 KVA step-down transformer
12   246   C
                 with a turns ratio of four to one if connected across a
                 440 volt line?
                 Large cable sizes are formed as individual conductors      obtain the             reduce the overall reduce the number all of the above
                 that may be comprised of several smaller strands to        flexibility required   weight of the wire of supports
                 __________.                                                for easy handling      run                needed for a
12   247   A                                                                                                          horizontal
                                                                                                                      overhead run



                                                                               19                                                        Electrical Questions-April 2009
Bk   Num   Ans                          Question                            Answer A          Answer B                     Answer C             Answer D             Illustr
                 The conversion of the throttle command voltage to the ahead or astern   feedback resistor             operational          long time constant
                 signal necessary to achieve the desired shaft RPM is function generator of the summing                amplifiers in the    amplifier circuit
12   248   A     accomplished by the __________.                       of the throttle   amplifier circuit             autorotation circuit
                                                                       control circuit

                 Figure "C" shown in the illustration represents a          silicon controlled    light emitting diode photosensitive         Zener diode
12   249   C                                                                                                                                                        EL-0078
                 __________.                                                rectifier                                  diode
                 The three devices which make up the circuit shown in       flip-flops            exclusive 'OR'       summing op amps        function
12   250   A                                                                                                                                                        EL-0087
                 the illustration are __________.                                                 gates                                       generators
                 The apparent power in a purely inductive circuit is also   true power            lead power           induced power          reactive power
12   251   D
                 known as __________.
                 The multiple prefix 'giga' (G) means __________.           thousand (10 to       million (10 to the   billion (10 to the     trillion (10 to the
12   253   C
                                                                            the 3rd power)        6th power)           9th power)             12th power)
                 Due to its construction, the component in figure "A"       Operates with         Its stable           Makes use of           Has very high
                 shown in the illustration has which of the listed          higher voltages       triggering voltage   inherent               input resistance
                 advantages compared to bipolar devices?                    and currents          makes it useful in   unidirectional         and uses
12   254   D                                                                allowing its use in   oscillators and      qualities serving      practically no gate   EL-0078
                                                                            high power            timing circuits.     as a controllable      current.
                                                                            amplifiers.                                rectifier.
                 Figure "B" shown in the illustration represents a/an   silicon controlled        junction field effect diac thyristor        IG MOS field effect
12   256   A                                                                                                                                                      EL-0067
                 __________.                                            rectifier                 transistor                                  transistor
                 Copper is often used as an electrical conductor        has high                  has a highly          is able to pass       holds insulation
12   257   C     because it __________.                                 resistance at low         polished surface      current with little   together well
                                                                        temperatures                                    opposition
                 Under which of the listed conditions can the engine    Any time it is            Only with the         After a 10 minute     Only after the
12   258   A     room retake the throttle control from the bridge of an deemed                    master's              delay to the input    throttle has been
                 automated vessel?                                      necessary.                permission.           command.              placed in stop.
                 The arrow drawn through the component shown in the is fixed and cannot           is variable           has yet to be         is not allowed to
                 illustration means that the device's value __________. be changed                between two limits determined for the       change during
12   260   B                                                                                                                                                        EL-0015
                                                                                                                        circuit application   circuit operation

                 The unit of apparent power in a purely inductive circuit   kva                   var                  emf                    watt
12   261   B
                 is called the __________.
                 A grounded switch or cable will be indicated by a          infinity              'zero'               being unsteady in      being unsteady in
12   262   B
                 megohmmeter reading of __________.                                                                    the high range         the low range
                 Regarding battery charging rooms, ventilation should       at the lowest point horizontally near      at the highest         only when
12   263   C     be provided __________.                                    of the room         the batteries          point of the room      charging is in
                                                                                                                                              progress
                 In a 15 HP induction-type motor with a cage rotor, the half the full load        equal to the full    five times the full    ten to twenty times
12   264   C     current required at standstill to produce starting torque current                load current         load current           the full load
                 is approximately __________.                                                                                                 current
                 If the clock frequency to the circuit shown in the        250 Hz                 666 Hz               6 kHz                  16 kHz
12   266   A     illustration were 2 kHz, what would be indicated at the                                                                                            EL-0087
                 output of 'FF-C'?
                                                                               20                                                       Electrical Questions-April 2009
Bk   Num   Ans                           Question                                 Answer A           Answer B              Answer C            Answer D             Illustr
                 A common type of protective covering used on                plain paper         rubber or plastic    silver sheathing     babbitt sheathing
12   267   B
                 electrical conductors is __________.
                 The main difference between an electron tube and a          type of function    reaction of          reaction of          reaction of
                 transistor is the __________.                               they can perform    electron flow        electron flow        electron flow
                                                                                                 through a gas or     through a            through a
12   268   D                                                                                     vacuum in a          semiconductor        semiconductor
                                                                                                 transistor           when placed in a     used to form a
                                                                                                                      tube                 transistor
                 If the values of C and R shown in the illustration were 1- 0.33 second          3 seconds            6 seconds            15 seconds
                 microfarad and 3-Megohms respectively, which of the
12   270   B                                                                                                                                                       EL-0086
                 listed intervals would equal one 'time constant'?

                 The ratio of the effective value of the counter EMF in     impedance factor capacitive               inductive            root mean square
12   271   C     volts, to the effective value of the current in amperes is                      reactance            reactance
                 called __________.
                 A generator has been exposed to water and is being         check for shorted take moisture           test insulation      ground the
                 checked for its safe operation. Therefore, it is           coils with a growler readings with a      values with a        commutator, or
12   272   C     necessary to __________.                                                        hydrometer           megger               slip rings and run it
                                                                                                                                           at half load for 12
                                                                                                                                           hours
                 Figure "C" of the diagram shown in the illustration has     64 volts            110 volts            190 volts            762 volts
                 a turns ratio of four to one. If a three-phase 440 volt
12   273   C     supply is connected to terminals 'A-B-C', what voltage                                                                                            EL-0084
                 should develop across terminals 'a-b-c'?

                 The speed of a three-phase squirrel-cage induction-         number of phases number of stator        locked rotor         resistance of the
                 type motor operating in a fixed frequency system is         to the motor     poles                   current              rotor winding
12   274   B
                 varied by changing the __________.

                 An across-the-line starter is typically used for which of   Reduced-current     Low torque           Low resistance       Full-voltage
12   275   D     the following applications?                                 starting of large   starting of small    starting of DC       starting of motors
                                                                             motors              motors               motors
                 The multiple prefix 'kilo' means __________.                thousand (10 to     million (10 to the   billion (10 to the   trillion (10 to the
12   276   A
                                                                             the 3rd power)      6th power)           9th power)           12 power)
                 An adjustable resistor, whose resistance can be             bleeder resistor    rheostat             bridge               variable shunt strip
12   277   B     changed without opening the circuit in which it is
                 connected, is called a __________.
                 The purpose of a heat sink, as frequently used with         prevent excessive compensate for         increase the         decrease the
12   278   A     transistors, is to __________.                              temperature rise  excessive doping       reverse current      forward current




                                                                               21                                                       Electrical Questions-April 2009
Bk   Num   Ans                          Question                                      Answer A              Answer B             Answer C           Answer D               Illustr
                 Batteries used for diesel engine starting should                be located in a       be located as        have sufficient     only be of the
                 __________.                                                     locker on the         close as possible    capacity to provide nickel alkaline type
                                                                                 weather deck          to the engine        at least 50 starts
12   279   B                                                                                                                consecutively
                                                                                                                            without recharging



                 The combined effect of inductive reactance, capacitive          reactance             total reactance      impedance              resonance
12   281   C     reactance, and resistance in an AC series circuit is
                 known as __________.
                 Before testing insulation with a megohmmeter, the               static charge of      armature will have insulation may be        insulation may be
                 windings of large machines should be grounded for               the machine may       a greater number damaged                    covered with
12   282   A
                 about 15 minutes just prior to the test, because the            give a false          of leakage paths                            moisture
                 __________.                                                     reading
                 The diagram shown in the illustration demonstrates              slowly at low         slowly at a high     rapidly at a low       rapidly at a high
                 one of the useful properties of an 'RC' time constant           current with a high   current with a low   current with a high    current with a high
                 circuit. The useful characteristic of the circuit is that "C"   "R" value and         "R" value and        "R" value and          "R" value and
12   286   A     can be charged __________.                                      discharged rapidly    discharged rapidly   discharged slowly      discharged slowly      EL-0086
                                                                                 at a high current     at a low current     at a high current      at a low current
                                                                                 with a low "R"        with a high "R"      with a low "R"         with a low "R"
                                                                                 value                 value                value                  value
                 In a DC series circuit, all the conductors have the             power expended in voltage drop             resistance to          current passing
12   287   D
                 same __________.                                                them              across them              current flow           through them
                 Which of the listed components does line "C"                    Grid              Plate                    Emitter                Collector
12   288   C                                                                                                                                                              EL-0068
                 represent for the transistor illustrated?
                 Battery charging rooms should be well ventilated                highly poisonous      highly combustible explosive gases          corrosive gases
12   289   C     because the charging process produces __________.               gas                   oxygen

                 Figure "D" shown in the illustration represents a/an            DIP IC chip           integrated          TO-5 flat pack          7-segment BCD
12   290   A     __________.                                                                           diac/triac envelope                         display                EL-0078

                 AC circuits develop resistance, inductance, and                 ohms                  mhos                 henrys                 farads
12   291   A     capacitance. The inductive reactance of a circuit is
                 expressed in __________.
                 When a megohmmeter is used to test insulation, the              good conductor        the leakage of       the inductive          the dielectric-
                 gradual rise of the pointer reading as a result of              resistance            current along the    reactance of the       absorption effect
12   292   D
                 continued cranking, is caused by __________.                                          surface of dirty     windings               of the insulation
                                                                                                       insulation
                 Which of the methods listed is used to maintain equal           The shunt fields      The shunt field      The series fields of   The series fields of
                 load sharing between two compound wound DC                      are                   rheostats are        both generators        both generators
12   293   D     generators operating in parallel?                               interconnected.       interconnected.      are connected in       are connected in
                                                                                                                            series.                parallel.


                                                                                   22                                                       Electrical Questions-April 2009
Bk   Num   Ans                           Question                               Answer A              Answer B             Answer C             Answer D            Illustr
                 The rotor slots of a repulsion-type motor are generally   produce a             permit a greater     permit a smaller      reduce eddy
12   294   A     skewed (placed nonparallel to the rotor axis) to          constant starting     air gap with the     air gap with the      current losses
                 __________.                                               torque                starter              starter
                 Shading coils are installed on AC full-voltage starters   eliminate contact     dissipate opening    delay current build   protect the motor
                 to __________.                                            chatter               contact arcs         up in the holding     windings from
12   295   A                                                                                                          coil                  momentary
                                                                                                                                            starting current
                                                                                                                                            overload
                 A silicon controlled rectifier (SCR) is a solid state     DC to AC and          AC to DC and         DC to AC and          AC to DC and
12   296   B     device used to change __________.                         control relatively    control relatively   control relatively    control relatively
                                                                           low load current      high load current    high load current     low load current
                 Which of the AWG wire sizes listed below would have       0000                  0                    14                    250
12   297   C
                 the smallest diameter?
                 The basic "control action" of a magnetic amplifier is     variations in the     changes in           the type of core      the construction of
12   298   B
                 dependent upon __________.                                load capacitance      inductance           material              the core
                 During the charging process of storage batteries, the     without ventilation   highly poisonous     highly explosive      without ventilation
                 charging rooms should be well ventilated because          excessive gassing     gases are            gases will            the battery will not
12   299   C     __________.                                               will occur            released             otherwise             take a full charge
                                                                                                                      accumulate

                 If the inputs to the diagram shown in the illustration 0,0                      0,1                  1,0                   1,1
                 were J=1, K=0, H=0, L=1, M=1, what logic levels would
12   300   D                                                                                                                                                       EL-0089
                 be indicated at points "X" and "Y" respectively?

                 Which of the listed figures shown in the illustration     A                     B                    C                     D
12   301   A     represents devices connected in a three-phase delta-                                                                                              EL-0084
                 delta arrangement?
                 When using a megohmmeter to test insulation, good         slight kicks of the a downward dip         a gradual rise in   the initial dip of the
                 insulation will be indicated by __________.               needle down scale followed by a            the pointer reading pointer
12   302   B                                                                                   gradual climb to       at the outset
                                                                                               the true resistance
                                                                                               value
                 Figure "D" of the diagram shown in the illustration has   64 volts            110 volts              190 volts             762 volts
                 a turns ratio of four to one. If a three-phase 440 volt
12   303   A     supply is connected to terminals 'A-B-C', what voltage                                                                                            EL-0084
                 should develop across terminals 'a-b-c'?

                 A three-phase, induction-type motor experiences an     Overspeed trip           Thermal overload     Three-pole safety     Magnetic blowout
                 open in one phase. Which of the listed automatic                                relay                switch                coil
12   304   B
                 protective devices will prevent the machine from being
                 damaged?
                 Most three-phase induction motors used for driving     resistor starters        across-the-line      impedance             reactor starters
12   305   B     engine room auxiliaries are started by __________.                              starters             starters

                                                                               23                                                     Electrical Questions-April 2009
Bk   Num   Ans                         Question                             Answer A            Answer B                     Answer C         Answer D               Illustr
                 When electrical cables penetrate watertight bulkheads, they should be     they must be bent            a watertight      they should be
                 __________.                                            grounded on either to a radius of six           stuffing tube     secured by a
                                                                        side of the        diameters                    capable of        clamp
12   307   C                                                            bulkhead                                        accepting packing
                                                                                                                        should be
                                                                                                                        employed
                 The purpose of an impressed current cathodic               prevent corrosion    neutralize the         protect engine        maintain a
                 protection system aboard ship is to __________.            of the hull,         vessel's stray         room and deck         minimum constant
                                                                            propeller, rudder    magnetic fields        machinery from        alternator load to
12   308   A                                                                and line shafting    which would            oxidation in the      prevent
                                                                                                 interfere with radar   presence of salt      overheating
                                                                                                                        air
                 Routine maintenance of lead acid batteries should          keeping the          coating cable          maintaining a         all of the above
12   309   D     include __________.                                        terminals clean      connections with       trickle charge
                                                                                                 petroleum jelly
                 Leads on the device in figure "B" shown in the             source, gate and     emitter, base and      emitter, base 1       anode, cathode
12   310   D                                                                                                                                                        EL-0067
                 illustration are named __________.                         drain                collector              and base 2            and gate
                 The process, whereby electrons gain sufficient energy      photo electric       secondary              thermionic            regressive
12   311   C     to be released from the surface of a thin, heated metal    emission             emission               emission              emission
                 plate, is known as __________.
                 Before testing insulation with a megohmmeter, the          insulation may be    insulation may be      armature windings     larger machines
                 windings of large machines should be grounded for          damaged              covered with           will have a greater   may acquire a
12   312   D     about 15 minutes just prior to the test as the                                  moisture               number of leakage     charge of static
                 __________.                                                                                            paths                 electricity during
                                                                                                                                              operation
                 A variable shunt, connected across the series field        divider              diverter               converter             rheostat
                 coils of a DC compound wound generator, to permit
12   313   B
                 adjustment of the degree of compounding, is called a
                 __________.
                 Across-the-line starters are used with AC motors to        reduced starting     regulated starting     high starting         controlled starting
12   315   C     provide __________.                                        current              current                torque                acceleration

                 The leads of the device in figure "B" shown in the         source, gate and     emitter, base and      emitter, base 1       anode, cathode
12   316   A                                                                                                                                                        EL-0065
                 illustration are named __________.                         drain                collector              and base 2            and gate
                 Electrical circuits are protected against overheating by   circuit breaker      amplifier              diode                 capacitor
12   317   A
                 means of a/an __________.
                 The function of a rectifier is similar to that of a        trap                 regulating valve       check valve           filter
12   318   C
                 __________.
                 The circuit shown in the illustration functions as a       pulse trigger circuit three stage, high     binary ripple         free running
                 __________.                                                for an operational gain class "A"           counter or shift      multivibrator
12   319   C                                                                                                                                                        EL-0087
                                                                            amplifier             amplifier             register

                 The multiple prefix 'tera' (T) means __________.           thousand (10 to      million (10 to the     billion (10 to the    trillion (10 to the
12   320   D
                                                                            the 3rd power)       6th power)             9th power)            12th power)
                                                                              24                                                           Electrical Questions-April 2009
Bk   Num   Ans                           Question                             Answer A              Answer B            Answer C             Answer D         Illustr
                 Most conducting materials such as copper, aluminum, increase in               increase in         decrease in          increase in
                 iron, nickel, and tungsten __________.                  resistance with       resistance with     resistance with      conductance with
12   321   A
                                                                         increased             decreased           increased            increased
                                                                         temperature           temperature         temperature          temperature
                 The electrician reports to you that he has obtained low motor be replaced     windings be dried   windings be          readings are
                 (but above 1 megohm) megger readings on the                                                       cleaned              acceptable
                 windings of a deck winch motor. Upon checking the
12   322   D     records of that motor, you find the readings have
                 consistently been at that level for the last six years.
                 You should, therefore, recommend that the
                 __________.
                 If the values of "C" and "R" shown in the illustration     0.33 second        3 seconds           6 seconds            15 seconds
                 were 1 microfarad and 3 Megohms respectively, at
12   326   D                                                                                                                                                 EL-0086
                 what listed time would "C" be considered fully
                 charged?
                 A circuit is protected from overheating by a/an            pyrometer          thermal overload    magnetic             overload
12   327   B
                 __________.                                                                   relay               contactor            transformer
                 The device in figure "A" shown in the illustration can     gates              emitters            substrates           cathodes
12   328   A                                                                                                                                                 EL-0078
                 sometimes have two __________.
                 Which of the following devices should be used to           Mercury            Alcohol             Thermocouple         Potentiometer
12   329   B
                 measure the temperature of a battery electrolyte?          thermometer        thermometer         pyrometer
                 Which of the wave shapes shown in the illustration is      A                  B                   C                    D
12   330   C                                                                                                                                                 EL-0088
                 termed a sinusoidal wave?
                 In a series circuit, which value will remain unchanged     Voltage            Current             Resistance           Inductance
12   331   B
                 at all places in the circuit?
                 If the pointer fails to return to zero when a megger is    pointer is stuck   hair springs are    megger is out of     megger is
12   332   D     disconnected, the __________.                                                 burned out          calibration          operating normally

                 Which of the following components are used to convert      Armature and       Commutator and      Rotor and            Field and exciter
12   333   B     alternating current produced in the generator windings     equalizer          brushes             interpoles
                 to direct current?
                 Which line of figure "A" shown in the illustration         W                  X                   Y                    Z
12   334   D                                                                                                                                                 EL-0088
                 represents the interval that the pulse is 'OFF'?
                 In electronic circuitry, the abbreviation 'PCB' commonly   pulse coded binary printed circuit     poly-coated braid     personal computer
12   335   B
                 means __________.                                                             board                                     bits
                 Line losses in a distribution circuit are kept to a        adding rubber      using higher        increasing the        using higher
                 minimum by __________.                                     insulation         current and lower   number of thermal voltage and lower
12   337   D
                                                                            conductors to the voltage              relays in the circuit current
                                                                            circuit
                 Which of the listed conditions describes the effect on     Capacitive         Conductivity will   Inductive            Resistivity will
12   338   B     intrinsic semiconductor operation as a result of a         reactance will     increase            reactance will       increase
                 temperature increase?                                      decrease                               decrease

                                                                                25                                                   Electrical Questions-April 2009
Bk   Num   Ans                            Question                                 Answer A          Answer B                   Answer C            Answer D             Illustr
                 The arrow drawn through the resistor shown in the            for use in low     a carbon                  a wire-wound type one whose
12   339   D     illustration indicates that it is __________.                power applications composition type                              resistance is            EL-0086
                                                                                                                                               variable
                 In electronic circuits, DC voltages can be positive (+)      printed circuit       chassis, console       analogue or digital all of the above
12   340   D     or negative (-) when measured with respect to the            board 'common'        frame or hull          circuitry 'common'
                 __________.                                                  trace                 'ground'               bus
                 The final step in testing a circuit for a ground involves    'zero'                infinity               steady in the high unsteady in the
                 the use of a megohmmeter. A grounded switch or                                                            range               low range
12   342   A
                 cable will be indicated by a megohmmeter reading of
                 __________.
                 Which of the following statements is true concerning         Compressed air        Magnetic brushes       The contact            Delicate parts
                 the cleaning of electrical contacts?                         should be used to     should be used to      surfaces should be     should be cleaned
                                                                              blow out metallic     remove metallic        greased to             with a brush and
12   344   D                                                                  dust.                 dust.                  increase contact       an approved
                                                                                                                           resistance.            safety solvent.

                 Which of the following describes the action when the         Full current is       Full line current is   Full line current is   Reduced line
                 handle is moved to the "start" position of a drum-type       supplied to the       supplied to the        supplied to the        current is supplied
                 motor controller used with a compound motor?                 shunt field, series   shunt and series       shunt field, and       to the shunt field,
                                                                              field, and            fields, and            reduced current is     series field, and
12   345   C                                                                  armature.             reduced current is     supplied to the        armature.             EL-0102
                                                                                                    supplied to the        series field and the
                                                                                                    armature.              armature.

                 The multiple prefix 'mega' (M) means __________.             thousand (10 to       million (10 to the     billion (10 to the     trillion (10 to the
12   346   B
                                                                              the 3rd power)        6th power)             9th power)             12th power)
                 To minimize magnetic field interaction between               parallel and as       at right angles and    parallel to and as     at right angles and
                 electrical conductors in physical proximity, it is best to   close as possible     as close as            far as practicable     as far as
12   347   D
                 keep them __________.                                        to each other         possible to each       from each other        practicable from
                                                                                                    other                                         each other
                 A nickel-cadmium battery is receiving a normal charge        be increased          be decreased           be cut off and the     remain the same
12   349   D     and gases freely. The charging current should                                                             battery allowed to
                 __________.                                                                                               cool
                 Figure "A" shown in the illustration represents a/an         magnetic amplifier Scott-T                   saturable-core         oil-filled toroid
12   350   C                                                                                                                                                            EL-0091
                 __________.                                                                     transformer               reactor
                 Reduced voltage applied to a motor during the starting       result in          lower the starting        cause a greater        increase the
                 period will __________.                                      decreased          current and               starting torque        starting current
12   351   B                                                                  acceleration time increase                                          and pump capacity
                                                                              only               accelerating time

                 Armature cores in a DC generator are made of                 fit the curvature of increase the            reduce eddy            allow for easy
12   353   C
                 laminated steel sheets to __________.                        the frame            hysteresis effect       current losses         assembly
                 The item referred to as a pigtail on a DC motor brush        feather spring       uninsulated wire        flexible spring        brush holder
12   354   B
                 rigging is a/an __________.                                                                               adjuster
                                                                                26                                                           Electrical Questions-April 2009
Bk   Num   Ans                         Question                                  Answer A          Answer B              Answer C            Answer D             Illustr
                 One purpose of a motor under-voltage protection            prevent automatic start the motor at a trip the load off the protect personnel
                 device is to __________.                                   restart when      very low voltage     motor in case of      from low voltage
12   355   A                                                                partial power is                       fire                  shocks
                                                                            restored

                 If the clock frequency to the circuit shown in the         10.1 kHz               12.5 kHz            805 kHz              1010 kHz
12   356   B     illustration were 100 kHz, what would be indicated at                                                                                           EL-0087
                 the output of 'FF-C'?
                 Which of the following components are used to              Lamp                   Starter             Ballast              All of the above
12   357   D
                 assemble a fluorescent lighting system?
                 A saturable-core reactor operates on the principle of      dielectric             permeability        reactance            inductance
12   358   B     controlling a load winding's inductance by varying the
                 core's __________.
                 RC time constant characteristics, as shown in the         bridge rectifiers for   timing and pulse                  motor controller
                                                                                                                       transistor power
12   359   B     illustration, are important in __________.                alternator              shaping circuits                  overload
                                                                                                                       amplifier biasing                         EL-0086
                                                                           excitation                                                protection
                 Operational amplifiers,used primarily in analog circuits, high input              high input       low input        low input
                 are characterized by __________.                          impedance, high         impedance, high impedance, low    impedance, high
12   360   A                                                               gain and low            gain and high    gain and high    gain and low
                                                                           output impedance        output impedance output impedance output impedance

                 Reversing the DC current flow through an electrical coil reduce the amount change its                 reduce the power     reverse its two-
12   361   D     will __________.                                         of flux produced  impedance                  consumed             pole field

                 In testing a three-phase delta winding for an open         test each phase    measure the             test the windings    open the delta-
                 circuit using a ohmmeter, you must __________.             with all           voltage across the      as parallel groups   connections to
12   362   D                                                                connections intact open connections        to avoid short       avoid shunting the
                                                                                               while testing           circuiting           phase being
                                                                                                                                            tested
                 The schematic symbol for an operational amplifier in       circle                 square              trapezoid            triangle
12   366   D
                 an analog circuit is a __________.
                 The total resistance of a parallel circuit is always       larger than the        smaller than the    equal to the sum one-half the sum
                 __________.                                                greatest branch        lowest branch       of the individual  of the individual
12   367   B
                                                                            resistance             resistance          branch resistances branch resistances

                 Which of the following expresses the relationship of       The output             The output          The output           The output
                 the input and output frequencies in a full wave            frequency is the       frequency is one-   frequency is twice   frequency is four
12   368   C
                 rectifier?                                                 same as input          half the input      the input            times the input
                                                                            frequency.             frequency.          frequency.           frequency.
                 In which section of the 24 VDC power supply circuit        I                      II                  III                  IV
                 illustrated, does the greatest change in voltage level
12   369   A                                                                                                                                                     EL-0085
                 take place when fed from ships power.


                                                                               27                                                     Electrical Questions-April 2009
Bk   Num   Ans                              Question                               Answer A              Answer B             Answer C               Answer D           Illustr
                 If the outputs marked "Q" of 'FF-A', 'FF-B' and 'FF-C' in 1, 0, and 1              1, 0, and 0          0, 0, and 1            0, 1, and 1
                 the circuit shown in the illustration are at logic levels 0,
12   370   B                                                                                                                                                           EL-0087
                 1, and 1 respectively, what levels are present at the
                 'NOT Q' outputs?
                 The direction of rotation of an induction motor is           opposite the          the same as the      determined by the determined by the
12   371   B     __________.                                                  rotating field        direction of the     number of poles   staggering of the
                                                                              direction             rotating field                         brushes
                 An insulation resistance reading is taken at 20°C and 2.5 megohms                  10 megohms           15 megohms        20 megohms
12   372   A     found to be 10 megohms. What would you expect the
                 resistance reading to be at 40°C?
                 A motor controller contains three selector push buttons will run                   will run until the   will not start until   will not stop unless
                 labeled 'start', 'jog', and 'stop'. When the 'jog' button is continuously after    'jog' button is      both the 'jog' and     the 'stop' button is
12   375   B     pushed, the motor __________.                                the 'jog' button is   released             'start' buttons are    pushed
                                                                              released                                   pushed

                 For more complete vessel protection when using an           all ship's service     machinery on deck    the hull's magnetic    straps connect the
                 impressed current cathodic system __________.               alternators have       and in the engine    fields are aligned     rudder with the
                                                                             additional             room is first        with a solid-state     hull and the
                                                                             temperature            coated with zinc     degaussing circuit     propeller shaft is
12   376   D                                                                 sensing devices        chromate before      using SCR's            grounded through
                                                                             and a thermal          final painting                              a slip ring/brush
                                                                             recorder installed                                                 arrangement

                 A 'dead front' switchboard is one __________.               without switches       with insulated    without circuit           without safety
                                                                             on it                  switches and no   breakers                  hand rails nor
12   377   B
                                                                                                    exposed terminals                           rubber mats

                 The device in figure "B" shown in the illustration will     base-emitter is        anode-cathode is     source-gate is         terminal 1-2 is
                 conduct when the __________.                                forward biased         forward biased       forward biased         forward biased
12   378   B                                                                 and the collector-     and the cathode-     and the gate-drain     and the emitter-       EL-0067
                                                                             base is reverse        gate is forward      is reversed biased     terminal 1 is
                                                                             biased                 biased                                      reverse biased
                 Mercury filled thermometers should never be used to         severe sparking        rapid oxidation of   contamination of       corrosion on the
                 determine the temperature of the battery electrolyte        and explosions         battery plates       the electrolyte        battery terminals
12   379   A
                 because accidental breakage of the thermometer can
                 cause __________.
                 When a solid-state component of an electronic circuit       prevent vibration      prevent          dissipate stray   act as a heat sink
                 is mounted to a metallic mass, the general purpose of       damage to              mechanical       magnetic currents
12   381   D     that mass is to __________.                                 delicate               damage to solid-
                                                                             components             state components



                                                                                28                                                         Electrical Questions-April 2009
Bk   Num   Ans                           Question                                Answer A             Answer B             Answer C           Answer D         Illustr
                 If the values of "C" and "R" shown in the illustration     0.1 second           0.2 second           0.5 second         5.0 seconds
                 were 1 microfarad and 100 kOhms, which of the listed
12   383   A                                                                                                                                                  EL-0086
                 time intervals would equal one 'time constant'?

                 What is the function of the interpoles installed in DC     To provide greater   To provide           To limit the       To limit the
                 motors?                                                    torque by            sparkless            production of      starting surge
                                                                            strengthening the    commutation          counter-           current.
12   384   B                                                                main field.          without having to    electromotive
                                                                                                 shift the brushes.   force.

                 Which of the wave shapes shown in the illustration is      A                    B                    C                  D
12   385   B                                                                                                                                                  EL-0088
                 termed a ramp or saw tooth wave?
                 The circuit shown in the illustration represents a/an      waveform analyzer Wheatstone              magnetic amplifier power supply and
12   386   D                                                                                                                                                  EL-0085
                 __________.                                                                  bridge                                     amplifier
                 The purpose of a main switchboard circuit breaker's        prevent main      protect the circuit     prevent alternator prevent low
12   387   C     reverse-power trip is to __________.                       circuit overload  breaker blowout         motorization       voltage trip out
                                                                                              coil
                 When charging lead-acid batteries, the charging rate       prevent damaging allow equalization       reduce lead        increase lead
12   389   A     should be reduced as the battery nears its full charge     battery plates    of cell voltages        sulfate deposits   peroxide formation
                 to __________.
                 Regarding an induction motor, the power developed by       power required to    speed required to   current flow in the torque developed
12   391   A     the rotor automatically adjusts itself to the              drive the load       drive the load      motor stator        by the rotating
                 __________.                                                                                                             field
                 You are testing the insulation in an AC generator with a   continue to rise as remain constant      continue to drop    stabilize after
                 megohmeter. The resistance value of a dry, clean           the test potential is as the temperature as the potential is approximately 2 to
                 winding will __________.                                   maintained,           of the windings    maintained,         4 minutes of
                                                                            becoming fairly       increases          becoming fairly     fluctuation
12   392   A                                                                steady as the                            steady after 5 to 7
                                                                            leakage current                          minutes
                                                                            stabilizes

                 Modern DC generators are fitted with commutating           prevent motorizing reduce sparking  reduce the load on reduce spring
12   393   B     poles to __________.                                                                           the main poles     pressure on the
                                                                                                                                   brushes
                 The purpose of a magnetic relay is to __________.        open a circuit only remotely open and provide            relay voltages at
                                                                          in the event of     close contacts    overcurrent        increased power
12   395   B
                                                                          overload                              protection during
                                                                                                                starting
                 A saturable reactor uses relatively small DC currents to high frequency low low frequency low high frequency      low frequency high
12   396   D     control __________.                                      power loads         power loads       high power loads power loads



                                                                                29                                                    Electrical Questions-April 2009
Bk   Num   Ans                            Question                           Answer A                 Answer B            Answer C             Answer D             Illustr
                 If a frequency of 16.8 kHz were measured at the output 8.4 kHz                   50.4 kHz            134.4 kHz            1680.0 kHz
                 of 'FF-C' of the circuit shown in the illustration, the
12   397   C                                                                                                                                                       EL-0087
                 clock frequency would be __________.

                 A signal derived from a controlled function and            monitoring signal     inverse signal      reverse signal       feedback signal
12   398   D     returned to the initiating point is called a/an
                 __________.
                 Routine maintenance of dry-type transformers should        cleaning the          measuring and       periodic cleaning    making sure that
                 include __________.                                        windings, if          recording the       of the winding       the units are close
                                                                            accessible, with a    winding             insulation with an   to bulkheads or
12   399   A                                                                vacuum cleaner or     temperature with    approved solvent     corners to protect
                                                                            very low pressure     an accurate                              them from damage
                                                                            air                   mercury
                                                                                                  thermometer
                 The sub-multiple prefix 'micro' (Greek letter 'mu')        thousandth (10 to millionth (10 to        billionth (10 to the trillionth (10 to the
12   400   B     means __________.                                          the -3rd power)   the -6th power)         -9th power)          -12th power)

                 A capacitor can be tested using a megohmmeter or an immediately swing            first swing quickly immediately          immediately swing
                 ohmmeter. If the meter is connected to a shorted    to the maximum               to 'zero', then     deflect to and       to a high reading
                 capacitor, the meter pointer should __________.     resistance value             gradually move up remain at zero         and then gradually
12   402   C                                                         for the capacitor            the scale as the                         decrease
                                                                                                  capacitor charges



                 A shaded-pole motor is classified as a __________.        synchronous            three-phase         DC compound-         single-phase
12   404   D
                                                                           motor                  induction motor     wound motor          induction motor
                 To provide its unique characteristics to analog circuits, voltage amp,           input amp, power    scaling amp,         differential amp,
12   406   D     the operational amplifier is made up of a/an              current amp and        amp and output      power amp and        voltage amp and
                 __________.                                               output amp             amp                 voltage amp          output amp
                 The part of the shipboard electrical system used to       bridge control         disconnect links    governor relay box   main switchboard
12   407   D     control the distribution of power to the branch circuits, panel
                 is the __________.
                 The amount of current flow required for the cathodic      amount of bare         speed of the ship   temperature of the all of the above
12   408   D     protection of a vessel is dependent upon the              steel surface          through the water   water
                 __________.
                 When mixing electrolyte for a lead-acid storage           distilled water intodistilled water into acid into the          acid into distilled
                 battery, you should pour the __________.                  the acid in a zinc- the acid in a glass distilled water in a    water in a glass
12   409   D
                                                                           plated container    container            zinc-plated            container
                                                                                                                    container
                 Figure "B" shown in the illustration represents a/an       magnetic amplifier Scott-T              saturable-core         oil-filled toroid
12   410   A                                                                                                                                                       EL-0091
                 __________.                                                                   transformer          reactor


                                                                              30                                                       Electrical Questions-April 2009
Bk   Num   Ans                              Question                              Answer A               Answer B              Answer C              Answer D           Illustr
                 In the illustration, if the device in figure "A" has a step- 0 volts                110 volts             11 volts              1100 volts
                 up ratio of 10 to 1, what voltage should be measured at
12   411   A     the secondary shortly after the primary of the device is                                                                                              EL-0059
                 connected to 110 volts DC current?

                 If the values of "C" and "R" shown in the illustration 0.1 second                   0.2 second            0.5 second            5 seconds
                 were 1 microfarad and 100 kOhms respectively, at
12   413   C                                                                                                                                                           EL-0086
                 what listed time would "C" be considered fully
                 charged?
                 The mica used in the commutators of DC machinery is harder than                     softer than copper the same                 softer than copper
                 __________.                                            copper                                          hardness as the          but wears away at
12   414   A
                                                                                                                        copper                   a slower rate

                 Which section of the circuit shown in the illustration       I                      II                    III                   IV
12   416   C     smoothes out highest degree of pulsations?                                                                                                            EL-0085

                 A switchboard for an AC electrical system requires the Frequency meter. Ohmmeter.                         Induction voltage  Current
12   417   A     use of which of the following devices?                                                                    regulator.         transformer
                                                                                                                                              governor.
                 When replacing a power transistor fitted with a heat         lubricate the          lubricate the heat    aid in the removal provide maximum
                 sink in a circuit, a coating of silicone grease is applied   transistor             sink                  of the heat sink   heat transfer
12   418   D
                 between the transistor case and the heat sink. This is
                 done to __________.
                 The charge of a lead-acid battery can be restored by         passing an             passing a direct      adding acid to the all of the above
                 __________.                                                  alternating electric   electric current      electrolyte
12   419   B
                                                                              current through        through the cell
                                                                              the cell
                 Which of the wave shapes shown in the illustration is        A                      B                     C                     D
12   420   D     termed a sharp pulse or spiked wave?                                                                                                                  EL-0088

                 The resistance of a conductor varies __________.             directly as its        inversely as its      directly as its       inversely as its
                                                                              length and             length and directly   length and directly   length and
12   421   A                                                                  inversely as its       as its cross-         as its cross-         inversely as its
                                                                              cross-sectional        sectional area        sectional area        cross-sectional
                                                                              area                                                               area
                 In an impressed current cathodic protection system,          connected to the       insulated from the connected to the         insulated from the
                 the anode is __________.                                     hull and               hull and does not hull but does not         hull but
12   423   B
                                                                              deteriorates with      waste away         waste away               deteriorates with
                                                                              time                                                               time
                 One function of the movable cams in a drum-type              regulate the speed     maintain              insulate the          limit the amount of
                 winch motor controller is to __________.                     of the motor           resistance            operating handle      load put on the
12   425   A
                                                                                                     contacts in clean                           motor
                                                                                                     condition

                                                                                  31                                                       Electrical Questions-April 2009
Bk   Num   Ans                             Question                                   Answer A              Answer B               Answer C              Answer D            Illustr
                 In the illustrated circuit, section II is considered to be a   full wave rectifier    half wave rectifier    quarter wave           short wave rectifier
12   427   A                                                                                                                                                                EL-0085
                 __________.                                                                                                  rectifier
                 In order to check the performance of a transistor              voltmeter or           impedance meter        ohmmeter or            sensitive
12   428   C     removed from its circuit, the instrument to be used            transistor tester                             transistor tester      potentiometer
                 should be a/an __________.
                 To test the state of charge of a nickel-cadmium battery,       ammeter                voltmeter              hydrometer             potentiometer
12   429   B
                 you should use a/an __________.
                 Section III of the circuit shown in the illustration is a      voltage regulator      filter                 rectifier              voltage
12   430   B                                                                                                                                                                EL-0085
                 __________.                                                                                                                         transformer
                 If a frequency of 2.5 kHz were measured at the output          0.8 kHz                2.5 kHz                7.5 kHz                20 kHz
12   431   D     of 'FF-C' in the circuit shown in the illustration, what                                                                                                   EL-0087
                 would be the clock frequency?
                 When a megohmmeter is being used to test insulation            dipping toward         continually rising     kicking slightly       fluctuating around
                 resistance, current leakage along the surface of the           zero then raising      as test voltage is     down scale as          a constant
12   432   C     insulation is indicated by the megohmmeter's pointer           slowly                 applied                voltage is applied     resistance reading
                 __________.

                 Which of the following types of DC motors has its field Counter EMF                   Shunt                  Salient pole           Series
12   434   B
                 connected in parallel with its armature?
                 Magnetic controller contacts may become welded          an open coil                  low contact            excessive ambient excessive
12   435   B     together during operation due to __________.                                          pressure               temperature       magnetic gap

                 Which of the following actions can be carried out in           Increase the       Install a heat sink. Shift the "Q" point          Increase the
                 order to prevent thermal runaway in a transistor?              current through                         to increase                  potential
                                                                                the collector-base                      collector current.           difference
12   438   B                                                                    junction.                                                            between the
                                                                                                                                                     emitter and the
                                                                                                                                                     base.
                 When checking the specific gravity of the battery              the battery is fully   the battery is         a hydrometer           warm
                 electrolyte with a hydrometer, you should be aware             charged when the       discharged when        reading is             temperatures will
                 that __________.                                               float sinks deepest    the float is highest   accurate if taken      lower the specific
12   439   D                                                                    into the electrolyte   in the electrolyte     immediately after      gravity of the
                                                                                                                              water is added to      electrolyte
                                                                                                                              the cell
                 Basic operating characteristics of the operational             differential input     power output           feedback circuit       supply voltages
12   440   C     amplifier such as gain and stability are the function of       stage                  stage
                 its __________.
                 Possible phase relationships between voltage and               Current and       Current may lead            Current may lag        All of the above.
12   441   D     current in an alternating current circuit include which of     voltage may be in the voltage.                the voltage.
                 the following conditions?                                      phase.
                 A suspected 'open' in a motor field winding can be             potentiometer     ohmmeter                    wattmeter              ammeter
12   442   B
                 tested by using a/an __________.
                 Insufficient brush pressure on a DC motor may cause            generator overload excess residual            water vapor            sparking of the
12   444   D
                 __________.                                                                       magnetism                  absorption             brushes
                                                                                   32                                                             Electrical Questions-April 2009
Bk   Num   Ans                           Question                           Answer A                Answer B             Answer C               Answer D          Illustr
                 Burning of controller contacts, when opening, is     coating the contact      magnetic blowout     an overvoltage         an overcurrent
                 prevented by __________.                             surfaces lightly         coils                release                release
12   445   B
                                                                      with petroleum
                                                                      jelly
                 The sub-multiple prefix 'nano' (n) means __________. thousandth (10 to        millionth (10 to     billionth (10 to the trillionth (10 to the
12   446   C                                                          the -3rd power)          the -6th power)      -9th power)          -12th power)

                 A switchboard, for a AC electrical distribution system,    Frequency meter. Ammeter                Voltmeter              All of the above
12   447   D     will be provided with which of the following
                 components?
                 Which of the procedures listed could result in              Applying incorrect Applying              Careless soldering   All of the above.
                 damaging a transistor beyond repair?                        polarity to the    excessive voltage which would
12   448   D
                                                                             collector circuit. to the input circuit. overheat the
                                                                                                                      transistor.
                 What is the polarity of voltage at point "Z" in the circuit It will always be  It will always be     It depends on the    It cannot be
                 shown in the illustration?                                  positive.          negative.             instantaneous        determined
12   449   A                                                                                                          polarity at point    without a             EL-0085
                                                                                                                      "W".                 voltmeter.

                 Basically, a magnetic amplifier is a saturable reactor     AC to the bias     variable             eddy current           a rectifier in the
12   450   D     with the addition of __________.                           winding            capacitance to all   protectors             load circuit
                                                                                               windings
                 Which of the electrical properties listed will always be Impedance            Current              Resistance             Voltage
12   451   D     the same across each component in a parallel circuit?

                 Which of the listed instruments can be best used to        Frequency meter    Megohmmeter          Voltmeter              Multimeter
12   452   B     locate a grounded field coil in a synchronous motor?

                 A generator is prevented from becoming motorized by        overspeed trip     reverse power        back pressure trip governor controls
12   453   B
                 the use of a/an __________.                                                   relay
                 Which type of AC single-phase motor will also operate      Split-phase        Series-wound         Shaded-pole            Repulsion-start
12   454   B
                 on direct current?
                 If the contacts of a motor starter or controller fail to   contacts are       contacts have        shading coil is        shading coil is
                 drop out when the 'stop' button is depressed, the          carrying excessive become welded        broken                 loose
12   455   B
                 __________.                                                current            together

                 Figure "A" of the diagram shown in the illustration        differential       saturable reactor    synchro system of magnetic amplifier
12   456   C     represents a __________.                                   transformer                             an engine order                              EL-0092
                                                                                                                    telegraph
                 Which section of the circuit shown in the illustration I                      II                   III               IV
12   457   B                                                                                                                                                     EL-0085
                 changes AC to DC?
                 A capacitor discolored due to excessive heat should be calibrated             replaced             cooled                 soldered
12   458   B
                 __________.
                                                                              33                                                      Electrical Questions-April 2009
Bk   Num   Ans                         Question                                  Answer A               Answer B          Answer C           Answer D                 Illustr
                 The standard procedure for maintaining the charge in        continuously          at least once each whenever the       whenever the
                 an emergency diesel starting battery is to trickle                                week               charge falls to    electrolyte specific
12   459   A     charge the battery __________.                                                                       75% of full charge gravity falls to
                                                                                                                                         1.250 or lower

                 Which of the wave shapes shown in the illustration is       A                     B                     C                     D
12   460   A                                                                                                                                                         EL-0088
                 termed a square wave?
                 A replacement wire having twice the length and one-         four times that of    twice that of the     the same as that one-half that of the
12   461   A     half the cross-sectional area of the original wire will     the original wire     original wire         of the original wire original wire
                 have a resistance that is __________.
                 Aboard ship, a grounded field coil in an AC motor can       portable growler      galvanometer          visual inspection     megohmmeter
12   462   D
                 be determined by using a __________.
                 The electrical energy necessary to power a sound-           the emergency         each station's        the emergency         normal 115 volt
12   463   B     powered telephone's small vibrating bell is obtained        batteries for the     hand-cranked          switchboard           DC supplies
                 from __________.                                            general alarm         generator
                 What is the purpose of the 'annunciator module'             Provide an input to   Drive the alarm       Deliver +5 and        Connect 24 volts
                 (6000F35) shown in the illustration?                        the set point         lamp and, through     +24 volts to their    to both sides of
12   464   B                                                                 module.               the controller, the   respective power      the horn.             EL-0094
                                                                                                   horn.                 supplies.

                 Grease coatings on electrical contact surfaces      small wire brush              compressed air jet clean dry cloth          10% solution
12   465   C     increase contact resistance and should be removed                                                                             carbon solvent
                 with a/an __________.                                                                                                         and water
                 Which of the referenced wave shapes would appear at A                             B                     C                     D
12   466   B     point "W" in the circuit shown in the illustration?                                                                                                 EL-0085

                 A ground in an electrical circuit outside the engine        cannot be         is of no                  is indicated at the   is indicated by the
                 room __________.                                            detected under    consequence to            branch circuit        ground detecting
12   467   D                                                                 normal conditions engineering               breaker panel         lamps on the main
                                                                                               personnel                                       switchboard

                 If a delicate component must be soldered into a circuit, operating the     using a thermal              pre-oxidizing the     coating the leads
                 the component may be protected from the heat of the soldering gun not shunt heat sink                   leads to be           to be soldered with
12   468   B     soldering process by __________.                         more than 60                                   soldered              a light oil film
                                                                          seconds at a time

                 As shown in the illustration, the circuit which 'shapes'    'pitch controller'    'error amplifier'     'function             'servo amplifier'
                 the linear output of the thrust lever so that the steady-                                               generator'
12   469   C                                                                                                                                                         EL-0095
                 state ship speed is linear with respect to that lever's
                 setting is the __________.
                 If the 'E/P converter' shown in the illustration operated   9 PSI                 15 PSI                18 PSI                24 PSI
12   470   C     on a range of 1-9 volts and 6-30 PSI, a 5 volt input                                                                                                EL-0096
                 would yield __________.

                                                                                 34                                                      Electrical Questions-April 2009
Bk   Num   Ans                           Question                                Answer A             Answer B               Answer C               Answer D           Illustr
                 If you disconnect and arrange both ends of a three          continuity of the   an infinite            the presence of a      that the conductor
                 conductor cable, without any contact between the            conductor           resistance             partial ground         is not short
12   471   A     individual conductors, a low ohmic value between the                                                                          circuited
                 ends of a single conductor would indicate
                 __________.
                 A testing device called a 'growler' is being used to        a loud growling     any vibration          the meter needle the meter needle
                 locate a shorted coil in the stator of an AC electrical     noise will be heard within the feeler      will be deflected to will be deflected to
12   472   A     machine. When the 'feeler' is moved over a slot                                 will cease             zero                 full-scale
                 containing the shorted coil __________.

                 A DC shunt generator has its field windings connected series with the           parallel with the      series with the   parallel with the
12   473   D     in __________.                                        series windings           field rheostat         armature windings armature windings

                 Controller contacts should be routinely cleaned by          blowing with        filing with a          wiping with a clean dressing with
12   475   C
                 __________.                                                 compressed air      bastard file           dry cloth           crocus cloth
                 The 'T-R' circuit of the system shown in the illustration   either "T" or "C"   either "B" or "R"      both "B" and "C"    both "T" and "R"
12   476   D     would become inoperative if a ground developed at                                                                                                    EL-0093
                 __________.
                 The third color band on a resistor is used to indicate      tolerance of the    number of zeros        first significant      second significant
                 the __________.                                             resistor            following the first    figure of the          figure of the
12   477   B                                                                                     two significant        resistance             resistance
                                                                                                 figures in the
                                                                                                 resistance value
                 Why is it a poor practice to use a high wattage             The circuit board   The foil wire may      The circuit board      The solder needs
                 soldering iron when soldering or desoldering                will blister and    become loose and       material may           to be kept to a dull
12   478   B     components on a printed circuit board?                      warp.               separate from the      become brittle.        heat dissipating
                                                                                                 circuit board.                                finish.

                 The sub-multiple prefix 'pico' (p) means __________.        thousandth (10 to millionth (10 to         billionth (10 to the trillionth (10 to the
12   480   D                                                                 the -3rd power)   the -6th power)          -9th power)          -12th power)

                 Which of the following statements concerning a simple The voltage drop          The total current      The total              The total voltage
                 parallel resistance circuit is correct?               across each               flow equals the        resistance equals      equals the sum of
                                                                       resistor is the           reciprocal of the      the sum of the         the individual
12   481   A                                                           same.                     sum of the             individual             voltages across
                                                                                                 individual currents.   resistances.           each resistance.

                 When troubleshooting AC motors, a portable growler          open field coils    grounded field         grounded stator        shorted stator coils
12   482   D
                 can be used for locating __________.                                            coils                  coils
                 The horizontal line which cuts across 'L1' shown in         iron core           saturable core         air gap                capacitive
12   483   B     figure "A" of the illustration indicates a/an                                                                                 coupling               EL-0091
                 __________.

                                                                               35                                                           Electrical Questions-April 2009
Bk   Num   Ans                         Question                                     Answer A         Answer B             Answer C              Answer D           Illustr
                 Impressed current cathodic protection is used on             fire alarm systems repeated painting    sacrificial zincs    vacuum tube
12   484   C     vessels instead of __________.                                                                                            degaussing
                                                                                                                                           systems
                 Which of the following methods should be used to             Filing               Burnishing          Sanding with 0000 All of the above
12   485   C
                 dress the face of silver-plated contacts?                                                             sandpaper           are correct.
                 A lead-acid battery may become hotter than normal            battery has a        charging voltage is specific gravity is battery room door
12   486   A
                 during a charge if the __________.                           shorted cell         too low             too high            is secured
                 The resistance value of a resistor in a circuit can best     single solid body    band markings on amperage value         physical size of
12   487   B     be determined by the __________.                             color of the         the resistor        written on the      the resistor
                                                                              resistor                                 resistor
                 On AC vessels, which of the following statements             A step-down          Vessel vibrations The voltage must Rectifiers cannot
                 represents the most difficult problem involved in            transformer is       affect the voltage be rectified and     operate with
12   488   C
                 obtaining a DC potential suitable for use by computer        always required.     source.             made ripple free. voltage regulators.
                 components?
                 Common basic applications for the operational                counting, pulsing    summing, scaling   step-up, step-         all of the above
                 amplifier include __________.                                and clocking         and difference     down and
12   490   B
                                                                              amplifiers           amplifiers         rectifying
                                                                                                                      amplifiers
                 Which of the substances listed can be used to shield         Glass                Mica               Bakelite               Permeable iron
12   491   D     sensitive equipment from static magnetic fields?

                 Handheld electrical phase sequence indicators are            preparing to         connecting lighting troubleshooting       connecting shore
12   492   D     useful when __________.                                      parallel alternators branch circuits     DC motors             power lines to the
                                                                                                                                             ship
                 A shunt-wound DC generator is one in which the shunt commutator                   brushes            armature               all of the above
12   493   D     field windings are in parallel with the __________.

                 The rotor of a synchronous motor operates in                 of the amortisseur the rotor is         the field strength the stator flux
                 synchronism with the rotating field because                  windings           magnetically         varies directly with rotates in the
                 __________.                                                                     locked into step     rotor slip           opposite direction
12   494   B                                                                                     with the rotating
                                                                                                 magnetic field by
                                                                                                 the excitation
                                                                                                 current
                 Which of the listed items will stop a motor due to a         Low voltage          Non-renewable      Renewable link         Low voltage
12   495   D     reduction in voltage and restart it when the voltage is      protection circuit   link fuse          fuse                   release circuit
                 restored to normal?
                 Section IV of the circuit shown in the illustration is the   voltage regulator    filter             rectifier              voltage
12   496   A                                                                                                                                                      EL-0085
                 __________.                                                                                                                 transformer
                 The timer element found in a reverse power relay             line voltage         the main bus       electromagnets         a separate battery
12   497   C
                 obtains its operating torque via __________.                                                                                source
                 Which section of the circuit is responsible for              I                    II                 III                    IV
12   500   D     maintaining a nearly constant voltage for all loads                                                                                              EL-0085
                 within its operating range?
                                                                                  36                                                      Electrical Questions-April 2009
Bk   Num   Ans                        Question                                  Answer A               Answer B          Answer C           Answer D                  Illustr
                 Hand-portable phase sequence indicators should be         installing a new       preparing to make replacing a        all of the above
                 used when __________.                                     synchroscope           the shore power   defective solenoid
12   502   B
                                                                                                  connection

                 The division of kilowatt load between two paralleled      amount of field        load-speed             amount of field       number of field
12   503   B     alternators is determined by the __________.              excitation to the      characteristics of     excitation to the     poles per
                                                                           leading machine        the governors          lagging machine       alternator
                 The set point current at which a magnetic-type            reduces magnetic       reduces magnetic       increases             increases
                 overload relay tends to trip may be increased by          force on the           force on the           magnetic force on     magnetic force on
                 turning the dashpot in the 'lower' direction. This action plunger and            plunger and            the plunger and       the plunger and
12   505   A     __________.                                               requires more          requires less          requires more         requires less
                                                                           current to trip the    current to trip the    current to trip the   current to trip the
                                                                           relay                  relay                  relay                 relay
                 The purpose of the bias winding in figure "B" shown in changing the              setting the            allowing the use of changing the
                 the illustration is for __________.                    direction of current      operating point of     either AC or DC in direction of current
12   506   B                                                                                                                                                         EL-0091
                                                                        in the control            the device             the load circuit    through the load
                                                                        winding
                 The timer element of a reverse power relay cannot be one generator is            the movement of the power flow is            the power flow is
                 energized unless __________.                           fully motorized           the disk is damped the same as the           the opposite to the
12   507   C                                                                                      by a permanent     tripping direction        tripping direction
                                                                                                  magnet

                 Before touching a small capacitor connected to a de-      gently tap the         tag it with a de-      be equipped with    short circuit the
                 energized circuit, or even one that is completely         body with a            energized tag          an insulated fuse   terminals to make
12   508   D     disconnected, you should __________.                      screwdriver                                   puller              sure that the
                                                                                                                                             capacitor is
                                                                                                                                             discharged
                 A breakable, mercury-filled thermometer should not be     severe sparking        rapid oxidation of     violent gassing at corrosion on the
                 used in a lead-acid battery to measure electrolyte        and explosions         battery plates         the positive plates battery terminals
12   509   A
                 temperature, as an accidental breakage can cause
                 __________.
                 What common shipboard system does figure "A"              Navigational           Engine order           Sound powered         Winch speed
12   510   B                                                                                                                                                         EL-0092
                 represent?                                                running lights         telegraph              telephone             control
                 Which of the following statements is true concerning      The total current      The total current      The total             The total voltage
                 simple parallel resistance circuits?                      flow equals the        flow equals the        resistance equals     equals the sum of
                                                                           sum of the             reciprocal of the      the sum of the        the individual
12   511   A                                                               individual currents.   sum of the             individual            voltages across
                                                                                                  individual currents.   resistance.           each resistance.




                                                                              37                                                         Electrical Questions-April 2009
Bk   Num   Ans                           Question                                Answer A               Answer B                Answer C            Answer D              Illustr
                 Which of the listed statements is correct when using        The pointer should    The pointer will        Ohmmeters are       All of the above.
                 an analog multimeter as an ohmmeter?                        be adjusted to        point to infinite       not sufficiently
                                                                             zero each time a      ohms when the           sized to accurately
                                                                             new resistance        meter is not in         measure
12   512   D                                                                 range is selected.    use.                    conductor
                                                                                                                           insulation
                                                                                                                           resistance.

                 Kilowatt load is divided between two AC generators          adjusting the         varying the             increasing both        decreasing both
                 operating in parallel by __________.                        governor controls     excitation voltage      prime mover            prime mover
12   513   A
                                                                                                                           speeds                 speeds
                                                                                                                           simultaneously         simultaneously
                 An increase in which of the listed conditions will          Frequency             Voltage                 Armature current       Inductance
12   514   A     increase the speed of a synchronous electric motor?

                 Before working on an electric cargo winch master            spray the gasket      drain condensate        open the circuit       heat the switch
                 switch or controller, you should __________.                surface with a        from the box            breaker in the         box to remove any
12   515   C
                                                                             solvent                                       power supply and       moisture
                                                                                                                           tag-out
                 The pushbutton on the handset of a ship's sound-            talk then released listen then                both talk and listen   ring the station
12   516   C     powered telephone must be depressed to                      to listen          released to talk                                  being called
                 __________.
                 What is the purpose of either 'set point module'            Program the          Supply 0 - 10 volts      Initiate logging of    Obtain an input
                 (6000F090/030) shown in the illustration?                   'signal conditioner' to the 'signal           measured               from the 'signal
                                                                             as to how to vary conditioner'.               information at set     conditioner' and, if
12   517   D                                                                 its input.                                    intervals; for         outside set limits,    EL-0094
                                                                                                                           example, each          signals the
                                                                                                                           hour.                  'annunciator'.
                 When troubleshooting an electronic circuit, a cold          reheat the circuit    reheat the              reheat connection do nothing as this
                 solder joint can be located with the aid of an              in an oven to an      connection with a       with a soldering  is the normal
                 ohmmeter. Once the problem has been located, you            even temperature      match and               tool and recheck condition
12   518   C     should __________.                                          and recheck with      recheck with an         with an ohmmeter
                                                                             an ohmmeter           ohmmeter

                 The 'function generator' of the control circuit illustrated can be                is used for             automatically    all of the above
                 __________.                                                 programmed to         controlling relay       selects which or
                                                                             produce a non-        contacts' positions     how many engines
                                                                             linear output for a   in selection circuits   are needed for a
12   520   A                                                                 linear input                                  required vessel                               EL-0095
                                                                             depending on                                  speed
                                                                             operating
                                                                             conditions

                                                                                38                                                          Electrical Questions-April 2009
Bk   Num   Ans                          Question                            Answer A             Answer B                Answer C             Answer D           Illustr
                 The frequency of an alternator at a given RPM is      number of turns of     number of             strength of the       output voltage
12   521   B     determined by the __________.                         wire in the            magnetic poles        magnets used
                                                                       armature coil
                 Which of the following methods should be used to test Test with an           Test with an          Use a growler,        Use a growler,
                 for an 'open' coil in an AC motor stator?             ohmmeter, one          ohmmeter with the     listening for noise   listening for noise
                                                                       test lead on the       test leads on the     and vibration to      and vibration to
12   522   B                                                           shaft, and the         disconnected          diminish when         increase when
                                                                       other test lead to     stator coil leads.    over an open coil.    over an open coil.
                                                                       the stator leads.

                 The illustrated circuits are similar to a __________.    megohm meter        Gauss meter           Wheatstone        germanium diode
12   523   C                                                                                                                                                    EL-0024
                                                                                                                    bridge            tester
                 If a three-phase induction motor malfunctions and      the motor will        more torque will      the motor will    the motor will
                 drops to a single-phase (one supply line open)         continue to run if it be developed          immediately stop  immediately stop
12   524   A     __________.                                            is not heavily                              and not be able toand can only be
                                                                        loaded                                      be restarted      restarted at no
                                                                                                                                      load
                 During its operation, loud buzzing and resultant       overheating of the low voltage on the low insulation          lubrication of the
12   525   B     welding of contacts of a magnetic relay may be caused contactor coil         operating coil       resistance to      contact bearing
                 by __________.                                                                                    ground             points
                 Although saturable reactors are extremely useful in    core hysteresis       inductive            IR drop throughout all of the above
12   526   A     some applications, their gain is low because of        losses                reactance in the     the load winding
                 __________.                                                                  control winding
                 In a three-phase circuit, the phase voltages are       120° apart            160° apart           180° apart         360° apart
12   527   A
                 __________.
                 A solid-state circuit is inoperative; the FIRST action wiggle all the        check all the        change all         check the DC
                 that should be taken is to __________.                 components to         resistors            transistors        supply voltage
12   528   D
                                                                        check for loose
                                                                        connections
                 Which of the problems listed will occur if a lead-acid The battery may       The electrolyte will The concentrated The separators will
                 battery is allowed to remain in a discharged condition be unable to          change to lead       sulfuric acid will harden.
12   529   A     for a long period of time?                             accept a full         sulfate.             attack the lead
                                                                        charge.                                    peroxide plates.

                 Which line in figure "A" shown in the illustration       W                   X                     Y                     Z
12   530   B                                                                                                                                                    EL-0088
                 represents the trailing edge of the wave?
                 The 'E/P converter' shown in the illustration receives a steady pressure     variable electrical   steady electrical     variable pressure
                 __________.                                              signal and          signal and            signal and            signal and
                                                                          produces a          produces a            produces an           produces a
12   531   B                                                              programmed          corresponding         inverse               corresponding         EL-0096
                                                                          electrical output   pressure output       temperature           electrical output
                                                                                                                    correction

                                                                             39                                                       Electrical Questions-April 2009
Bk   Num   Ans                          Question                                  Answer A            Answer B               Answer C               Answer D         Illustr
                 What type of current would flow through the load in          AC only              DC only               AC or DC              AC or DC
                 figure "B" shown in the illustration?                                                                   depending on          depending on
12   532   B                                                                                                             control winding       instantaneous        EL-0091
                                                                                                                         polarity              polarity of the
                                                                                                                                               source
                 The division of the kilowatt load between two AC             voltage regulators field rheostats         reverse power         prime mover
                 generators operating in parallel is controlled by the                                                   relays                governors
12   533   D
                 settings and characteristics of the __________.

                 Most three-phase induction motors of five horsepower         autotransformer      resistor starters     across-the-line       reactor starters
12   534   C
                 or less, are started by __________.                          starters                                   starters
                 If a magnetic controller relay fails to drop out when the    excessive spring     overvoltage           excessive current     welded contacts
12   535   D     coil voltage is removed from the relay, the probable         tension
                 cause may be __________.
                 How many different D.C. voltages are required to             Two                  Three                 Four                  Five
12   536   C                                                                                                                                                        EL-0094
                 operate the circuit shown in the illustration?
                 The circuit shown in the illustration represents a           battery charging     synchronous           depth sounding        cathodic protection
12   537   D     __________.                                                  circuit              exciter               unit                  system              EL-0090

                 When troubleshooting electronic equipment, the FIRST set the meter to             check the voltage     remove the            check the current
                 step to be taken before testing the circuit voltage is to the lowest range        supply from the       suspected             flow through the
12   538   B
                 __________.                                                                       power source          component             circuit

                 When charging a 100 amp-hour lead-acid battery,              the temperature of   the charging rate     the source of         gassing within the
                 __________.                                                  the electrolyte      should be no          power for charging    battery decreases
                                                                              should not be        greater than 125%     should be 2.5 volts   when nearing full
                                                                              allowed to exceed    of the battery amp-   per cell              charge and it will
                                                                              90°F                 hour rating                                 be necessary to
12   539   C                                                                                                                                   reduce the
                                                                                                                                               charging current
                                                                                                                                               to a low finishing
                                                                                                                                               rate


                 Section II of the circuit shown in the illustration is the   voltage regulator    filter                rectifier          voltage
12   540   C                                                                                                                                                        EL-0085
                 __________.                                                                                                                transformer
                 The only point in the steering stand shown in the            repeater assembly steering wheel           operation selector course selector
12   541   B     illustration which needs periodic lubrication is the         ball bearings     bearing                  switch             pointer                 EL-0098
                 __________.




                                                                                40                                                         Electrical Questions-April 2009
Bk   Num   Ans                         Question                                   Answer A              Answer B              Answer C              Answer D           Illustr
                 When testing a capacitor with an analog type                there is no meter     the meter deflects    the meter deflects    the meter deflects
                 ohmmeter, a good capacitor will be indicated when           deflection            to a low resistance   to a low resistance   to a low resistance
                 __________.                                                                       value and remains     value and slowly      value and
12   542   C                                                                                       there                 increases towards     increases rapidly
                                                                                                                         infinity              to a higher value,
                                                                                                                                               but stays fairly low

                 The division of kilowatt load between two paralleled        amount of field       load-speed            amount of field       type of alternator
12   543   B     alternators is determined by the __________.                excitation of the     characteristics of    excitation to the
                                                                             leading machine       the governors         lagging machine
                 The synchronous speed of an induction motor is the          speed at which the    speed of the          frequency of the      slip in per cent of
12   544   B
                 __________.                                                 rotor turns           rotating field        rotor current         rotor RPM
                 As shown in the illustration if the applied voltage is 12   0.6 amp               0.833 amp             1.2 amps              2.4 amps
                 VDC, the resistance of R1 is 10 ohms, and R2 is 10
12   545   A                                                                                                                                                          EL-0036
                 ohms what is the current flowing through R2?

                 In a simple series circuit, the entire source voltage will the resistor next to   a shorted             the resistor next to an open circuit
12   546   D     be present across __________.                              the negative           component             the positive                                 EL-0020
                                                                            terminal                                     terminal
                 Which line in figure "A" shown in the illustration         W                      X                     Y                    Z
12   548   C                                                                                                                                                          EL-0088
                 represents the interval that the pulse is 'ON'?
                 The charging of lead-acid storage batteries will always dangerous acid            a dangerously         the danger of lead all of the above
12   549   B     result in __________.                                      burns                  explosive gas         poisoning
                                                                                                   being liberated
                 When the current flow through a power transmission          is halved             is doubled            is quadrupled         remains the same
12   551   C     line is doubled, the power loss __________.

                 While troubleshooting a circuit in an engine room           Correct polarity      Meter leads must      Resistor's circuit    The meter case
                 central control console, a resistor is suspected of being   must be observed      not be twisted so     must be de-           must be grounded
                 faulty. Which of the following precautions must be          because reverse       as to cancel out      energized and at      prior to attaching
12   552   C     observed if an ohmmeter is to be used to check its          bias will damage      the individual        least one end of      the leads.
                 value?                                                      the component.        magnetic fields.      the component
                                                                                                                         isolated.

                 Which of the following procedures should be used to         Multiply the          Divide the total      Multiply the          Divide the total
                 determine the load of a three-phase, delta wound, AC        amperage in one       amperage in all       amperage in one       amperage in all
12   553   C     generator?                                                  phase by three.       phases by three.      phase by the          phases by the
                                                                                                                         square root of        square root of
                                                                                                                         three.                three.
                 An across-the-line starter provides __________.             maximum torque        slow starting         high speed            reduced voltage
12   554   A
                                                                                                   power
                 Excessive heat in an operating motor controller can         a closed starter      loose connections missing arc chutes low motor starting
12   555   B
                 result from __________.                                     contact                                                    torque
                                                                               41                                                        Electrical Questions-April 2009
Bk   Num   Ans                            Question                              Answer A                Answer B                Answer C           Answer D           Illustr
                 The fluctuation of voltages in figure "A" and "D" of the    wave                  ripple                roll                  swell
12   556   B     circuit shown in the illustration is called __________.                                                                                             EL-0085

                 Transformers are used onboard ships with AC                 change line           increase power        decrease power        provide different
                 generators to __________.                                   frequency value       output to             output to             voltage values to
                                                                                                   modulating            modulating            operate various
12   557   D                                                                                       frequency             frequency             types of electrical
                                                                                                   controllers           controllers           equipment.

                 A full-wave rectifier has one diode burned out in an        Zero                  Half-wave rectified Full-wave rectified Equal to the AC
12   558   B     open condition, what will be the output characteristic of                                                                 input
                 the device?
                 Considering the function of the circuit shown in the        To select which       So the circuit can    To provide an         So as to
                 illustration, what is the purpose of supplying the thrust   lever (bridge or      differentiate         alternate voltage     automatically
12   559   B     lever potentiometers with both (+) and (-) 15 volts?        engine room) is       between ahead         supply if the other   select the position   EL-0095
                                                                             active.               and astern            fails.                of Relay #1.
                                                                                                   commands.
                 What is the total power consumed by the illustrated         2 watts               12 watts              48 watts              288 watts
                 circuit if the supply is 24 volts and the resistances of
12   560   C                                                                                                                                                         EL-0020
                 R1 is 3 ohms, R2 is 4 ohms, and R3 is 5 ohms?

                 The full load torque of an electric motor is the            minimum torque        turning moment        maximum torque        turning moment
                 __________.                                                 developed by the      exerted by the        developed by the      exerted by the
                                                                             motor accelerating    motor at rated load   motor with rated      motor from any
12   561   B                                                                 from stop to full     and speed             voltage and           rotor angular
                                                                             speed                                       frequency             position at any
                                                                                                                                               load
                 Prior to using an analog type ohmmeter, the leads are       The lead clips        The batteries         The test reading      The test reading
                 purposely shorted together. Which of the following          should be             should be             should be added       should be
12   562   B     actions should be taken if, when adjusting to 'zero'        replaced.             replaced.             to each final         subtracted from
                 ohms, the indicating needle can not be returned to                                                      reading.              each final reading.
                 'zero' on the scale?
                 What is the purpose of each of the 'signal conditioners'    Convert the           Drive the Data and    Supply two or         Receives
                 (6000F085 / AH170 / F125) shown in the illustration?        varying signal from   Alarm Loggers         three different       constantly updated
                                                                             its particular        directly for a        D.C. voltages to      information from
                                                                             sensor and deliver    continuous record     their respective      the 'set point
                                                                             a corresponding       of sensor             motors which in       module' in order to
12   563   A                                                                 signal of 0 - 10      operating             turn rotates to       keep the pressure     EL-0094
                                                                             volts to the 'set     conditions during     indicate relative     or temperature at
                                                                             point module'.        the time the          input conditions.     its sensor at set
                                                                                                   engine(s) may be                            limits.
                                                                                                   on-line.


                                                                               42                                                          Electrical Questions-April 2009
Bk   Num   Ans                        Question                                  Answer A           Answer B           Answer C               Answer D           Illustr
                 The speed of a wound-rotor induction motor               will be fixed by the can be varied by a can only be            can only attain
                 __________.                                              number of field      rheostat-type      synchronous            synchronous
12   564   B
                                                                          poles                control            speed at full load     speed at no load

                 If you hear a loud buzzing noise coming from a           assume that the    assume that the    notify the               feel the outside of
                 magnetic motor controller, you should __________.        motor is operating controller is      electrician or           the casing with
12   565   C
                                                                          at a full load     operating normally watch engineer of        your hand to see if
                                                                                                                the problem              it is hot
                 Using illustrated chart, when will the power factor be   When the motor is When the            When there is no         the power factor is
                 least efficient?                                         operating at full  percentage of slip load on the motor.       the same from no-
12   566   C                                                                                                                                                   EL-0006
                                                                          load.              is greatest.                                load to locked
                                                                                                                                         rotor.
                 The function of the autotransformers used with the       increased voltage increased torque        reduced voltage      speed control
12   567   C     starters of large AC motors is to provide __________.    for starting      for starting            for starting

                 When lead-acid batteries are charging, they always       considered inert    highly explosive      extremely toxic      heavier than air
12   569   B
                 give off hydrogen gas that is __________.
                 The resistance of most conducting materials will         increase as         decrease as           remain the same      remain the same
12   571   B     change as a result of temperature change. The            temperature         temperature           between 20°F and     between 68°F and
                 resistance of copper will __________.                    decreases           decreases             110°F                230°F
                 How will the value of the output frequency change if     It will remain      It will decrease by   It will become       It will increase.
12   573   D     the load is removed from a turbo generator having a      unchanged.          approximately 3%.     variable.
                 governor speed droop setting of 3%?
                 Reversing any two of the three rotor leads on a wound-   increase motor      decrease motor        reverse the motor have no effect on
                 rotor induction motor will __________.                   performance         performance           rotation          the direction of
12   574   D
                                                                                                                                      rotation or motor
                                                                                                                                      performance
                 If the steering stand selector switch is allowed to     not respond to       move in one           respond only to   stop moving only
                 remain in the 'Non-Follow-up' mode after testing of the commands from        direction only        the output of the when the helm is
                 steering gear, the rudder will __________.              the helm             regardless of the     differential      counter-rotated to
12   576   A                                                                                  movement of the       repeater          put the pump at          EL-0097
                                                                                              helm                                    neutral stroke

                 The function of a step-down potential transformer is to voltage and         voltage and            current and          power
12   577   B     reduce the load __________.                             current             increase line          increase line
                                                                                             current                voltage
                 To avoid damaging the components of a printed circuit ground the board avoid reversing             isolate sensitive    all of the above
12   578   B     board when testing it with a DC volt-ohmmeter, you                          the polarity of the    components with
                 should __________.                                                          leads                  heat sinks
                 In actual applications, electrical connections to 'R1-R2' soldered contacts spliced and taped      slip rings and       solderless crimp-
                 of figure "A" and to 'R1-R2-R3' of figure "B" shown in                      connections            brushes              on connectors
12   579   C                                                                                                                                                   EL-0092
                 the illustration are made by __________.


                                                                             43                                                       Electrical Questions-April 2009
Bk   Num   Ans                           Question                                  Answer A              Answer B              Answer C              Answer D          Illustr
                 The component labeled 'CR1' in the circuit shown in          varies its            rectifies the          acts as a low        establishes a
                 the illustration __________.                                 anode/cathode         varying voltage        capacitive           constant reference
12   580   D                                                                  polarity depending    from the collector     reactance to         voltage for the       EL-0085
                                                                              on 'RL' current       of 'Q1'                smooth ripple        base of 'Q1'

                 A resistor placed in parallel to the output of a power       is a temperature      corrects power         prevents           aids in output
12   581   D     supply __________.                                           compensator           factor                 excessive currents voltage regulation

                 As load is added to an AC generator provided with            lowering frequency increasing                increasing        lowering frequency
                 constant field excitation, the prime mover slows down        and lowering       frequency and             frequency and     and increasing
12   583   A     with the effect of __________.                               generated voltage increasing                 lowering          generated voltage
                                                                                                 generated voltage         generated voltage

                 A characteristic of an induction motor with a low            high starting         high starting          high slippage        low starting
12   584   B
                 resistance rotor winding is __________.                      voltage               current                                     voltage
                 How many modes of rudder positioning are available           One                   Two                    Three                Four
12   586   C     using the steering stand shown in the illustrations?                                                                                                 EL-0098

                 In troubleshooting a circuit in a console, you find that a   Correct polarity      Meter leads must       The meter must be    The resistor's
                 resistor may be faulty. Which of the precautions listed      must be observed,     be twisted to          placed in series     circuit must be de-
                 must be observed when using an ohmmeter to carry             connecting the red    cancel the leads'      with the resistor    energized and at
12   588   D     out this test?                                               lead to the           magnetic fields.       and the circuit.     least one end of
                                                                              banded end of the                                                 the component
                                                                              resistor.                                                         isolated.

                 The state of charge of a lead-acid battery is best           individual cell       ampere-hour            electrolyte specific total cell voltage
12   589   C
                 indicated by the __________.                                 voltage               capacity               gravity
                 The most inefficient method of voltage reduction from        capacitor in series   inductor in series     capacitor and        resistor in series
                 the stand point of power loss, is a/an __________.           with the load         with the load          inductor in series with the load
12   591   D
                                                                                                                           with the load

                 Which is a function of the voltage regulators used with To cut out                 To cut in additional   To divide the KW     To divide reactive
                 AC generators?                                          generators when            generators             load equally         current between
                                                                         they are no longer         automatically as       between              generators
12   593   D                                                             required.                  required.              generators           operating in
                                                                                                                           operating in         parallel.
                                                                                                                           parallel.
                 If an induction motor were to be operated at 90% rated there would be an           starting current       synchronous          the slip would
12   594   D     voltage, __________.                                    increase in starting       would increase         speed would          increase
                                                                         torque                     slightly               decrease slightly
                 When troubleshooting a magnetic controller, it is found excessive                  high ambient           low voltage on the   high voltage on
12   595   C     that the contacts are welded together. The most         operation at low           temperature            operating coil       the operating coil
                 probable cause is __________.                           load

                                                                                44                                                         Electrical Questions-April 2009
Bk   Num   Ans                           Question                                   Answer A          Answer B             Answer C              Answer D          Illustr
                 The purpose of a 'slew rate controller' in a circuit such    limit the rate of  introduce a 'live    shape the linear      reduce air
                 as shown in the illustration is to __________.               change of a signal zero' factor into    input into a non-     pressure to a
12   596   A                                                                                     the circuit          linear output         value required by     EL-0096
                                                                                                                                            a combination
                                                                                                                                            circuit
                 If both the 'high level' and 'low level' alarms come on      sensor failure      failed alarm        low level             extremely high
                 for the same address of a centralized control console,                                                                     level
12   598   A
                 the most likely problem is a/an __________.

                 The voltage at the reference electrode of the circuit        class A detector    operational         amplitude             magnetic amplifier
                 shown in the illustration is applied to the input of a/an    whose output        amplifier whose     modulator whose       whose output
                 __________.                                                  drives an           output controls a   output drives an 2-   controls a
12   599   D                                                                  autotransformer     step-up voltage     stage isolation       saturable reactor     EL-0090
                                                                                                  reactor             transformer

                 Erratic operation of the device represented in the           improper contact a low three-phase improper contact a high three-phase
                 diagram labeled "A" shown in the illustration could be       at "R" slip rings or voltage supply at "S" slip rings or voltage supply
12   600   A                                                                                                                                                      EL-0092
                 traced to __________.                                        "S" connections                     "R" connections

                 A transformer works on the basic principle of                self impedance     attraction and      mutual induction       increasing power
12   601   C
                 __________.                                                                     repulsion
                 Before measuring an unknown resistance with an               adjust the meter's short the test      change the             center the meter's
                 ohmmeter, you should __________.                             pointer to mid-    leads and calibrate meter's batteries      pointer at infinity
12   602   B                                                                  scale              the meter reading
                                                                                                 to 'zero'

                 The instantaneous reduction in voltage of an AC          droop              drop                     dip                   regulation
                 generator, resulting from an increase in load, and prior
12   603   C
                 to the automatic voltage regulator correcting the
                 situation, is called voltage __________.
                 A characteristic of a wound-rotor induction motor, with low starting torque high starting            high speed            low starting
12   604   B     a high resistance rotor winding, is __________.                             torque                                         voltage

                 The diagrams shown in the illustration represent a/an        engine order        rudder angle        engine speed          sound powered
12   605   D     __________.                                                  telegraph circuit   indicator           tachometer with       telephone system      EL-0093
                                                                                                  arrangement         repeaters
                 In the illustration, the voltage applied to the circuit is 12 0.6 watts          3.6 watts           7.2 watts             120 watts
                 VDC, the resistance for R1 is 10 ohms, and R2 is 10
12   606   B                                                                                                                                                      EL-0036
                 ohms. What is the power consumed in 'R1' of the
                 circuit shown in the illustration?



                                                                                 45                                                   Electrical Questions-April 2009
Bk   Num   Ans                           Question                                  Answer A             Answer B              Answer C             Answer D          Illustr
                 The potentiometers shown in the illustration are             so there is always   because one           to command or        because one
                 supplied with both (+) and (-) voltages as well as a         a spare power        supply is for pitch   indicate pitch       supply is for pitch
                 reference to ground __________.                              supply on standby    command, the          direction in         command, the
                                                                              which is grounded    other for lever       addition to amount   other for relay
                                                                              for safety           illumination at       of pitch             operation and the
12   607   C                                                                                       night and the                              potentiometers are    EL-0095
                                                                                                   potentiometers are                         in positions where
                                                                                                   in positions where                         they can be
                                                                                                   they can be                                accidentally
                                                                                                   accidentally                               touched
                                                                                                   touched
                 You have installed a Zener diode in parallel with a          is working as it     is shorted            is open              does not regulate
                 load. While measuring the voltage across the Zener           should                                                          as it should
12   608   A     diode it is found that it does not change as the current
                 through the load increases. This means that the Zener
                 diode __________.
                 Violent gassing from a lead-acid battery while it is         plate separators     battery               electrolyte specific charging rate is
                 being charged, indicates that the __________.                are grounded         compartment           gravity is too low too high
12   609   D
                                                                                                   ventilation is
                                                                                                   inadequate
                 Assuming a standard 60 Hz. input to the circuit shown        30 Hz                60 Hz                 90 Hz                120 Hz
12   610   D     in the illustration, the ripple frequency would be                                                                                                 EL-0085
                 __________.
                 What controls the rudder when the 'operation selector        Non-follow-up        Gyro-compass          Course selector      Steering wheel
12   611   D     switch' of the steering stand shown in the illustration is   controller                                 pointer                                    EL-0098
                 in the 'HAND' position?
                 An ohmmeter can be used to measure __________.               the amount of        voltage between       circuit continuity   circuit power
12   612   C                                                                  current flow in a    two points in a
                                                                              circuit              circuit
                 Which sensor shown in the illustration develops its          Transducer           Resistance            Pressure Switch      Thermocouple
12   613   C     own conditioning and point setting and 'reports' directly                         Temperature                                                      EL-0094
                 to the 'annunciator'?                                                             Detector (RTD)
                 Under normal conditions, the speed of a two-speed            frequency of the     resistance in the     number of field      amplitude of the
12   614   C     squirrel cage induction motor is changed by varying          applied voltage      rotor circuit         poles                applied voltage
                 the __________.
                 Magnetic controller contacts may become welded               excessive            low contact           an open coil         excessive ambient
12   615   B     together during operation because of __________.             magnetic gap         pressure                                   temperature

                 What is the power consumed by 'R1' in the circuit           2 watts               3 watts               6 watts              12 watts
                 illustrated if the supply is 24 volts and the resistance of
12   616   D                                                                                                                                                        EL-0020
                 R1 is 3 ohms, R2 is 4 ohms, and R3 is 5 ohms?

                 If a transformer is connected to a DC source, the            contacts             primary coil          secondary coil       core
12   617   B
                 transformer will overload at the __________.
                                                                                46                                                         Electrical Questions-April 2009
Bk   Num   Ans                       Question                            Answer A              Answer B                    Answer C             Answer D         Illustr
                 A burned-out LED should be indicated by __________. excessive output     a slight glow in the        excessive            no illumination
12   618   D
                                                                                          crystal                     illumination
                 The basic operating principle of a transformer is       electromagnetic  variance of a               mutual reaction      thermionic
12   621   A     attributed to __________.                               induction        conductor in a                                   emission
                                                                                          magnetic field
                 The output voltage of a 440 volt, 60 Hz AC generator is load on the      load on the prime           speed of the prime   exciter output
12   623   D
                 controlled by the __________.                           alternator       mover                       mover                voltage
                 Motor controller or starter contacts may become pitted open under loaded close slowly with           open too quickly     close quickly with
                 and welded together if the contacts __________.         conditions       light pressure              and arc              proportionate
12   625   B
                                                                                                                                           pressure

                 If coil 'R1-R2' at the receiver of figure "A" shown in the No action is        Reverse 60 Hz         Interchange         Interchange
                 illustration turned opposite of that in the transmitter,   necessary as this   supply                connections to 'S1' connections to 'S1'
12   626   D                                                                                                                                                    EL-0092
                 what corrective action should be taken?                    is normal           connections to 'R1'   and 'S2'.           and 'S3'.
                                                                            operation.          and 'R2'.
                 Transformer cores are laminated to reduce                  eddy currents       secondary flux        leakage flux         all of the above
12   627   A
                 __________.
                 When using an ohmmeter to test a semiconductor             open                short                 good resistive       good capacitive
                 diode, you find a low resistance in both the forward and                                             quality              quality
12   628   B     reverse bias directions. This indicates that the diode
                 has a/an __________.

                 The capacity of a storage battery is measured in           volts               ampere-hours          farads               amps
12   629   B
                 __________.
                 Power necessary to operate the horn shown in the           comes from each     is supplied from a is conducted            also lights lamps
12   630   B     illustration __________.                                   station's magneto   115 volt source    through a relay         "R" and "T"          EL-0093
                                                                                                                   coil
                 When placed in a magnetic field, which of the              Glass               Bakelite           Soft iron               Aluminum
12   631   C     materials listed will maintain the highest permeability?

                 Before measuring an unknown resistance with an             adjust the meter's change the             center the meter's short the test
                 ohmmeter, you should __________.                           pointers to mid-   meter's batteries      pointer at infinity leads and calibrate
12   632   D
                                                                            scale                                                         the meter

                 The governor control switch of an alternator is moved      raise the no-load   raise the             lower the no-load    lower the
                 to the 'raise' position. This action will __________.      speed setting of    percentage of         speed setting of     percentage of
12   633   A
                                                                            the governor        speed droop           the governor         speed droop

                 Which of the following statements is true concerning       Rotor slip is       An increase in     A decrease in           A decrease in
                 the operating characteristics of a basic squirrel-cage     dependent upon      motor load results rotor speed results     rotor speed
12   634   A     induction motor?                                           the motor load.     in less slip.      in less generated       produces a
                                                                                                                   current.                weaker magnetic
                                                                                                                                           field.

                                                                              47                                                        Electrical Questions-April 2009
Bk   Num   Ans                            Question                              Answer A             Answer B              Answer C              Answer D           Illustr
                 The meter indicating the position of the 'bridge Thrust   in the Engine        on the Bridge         in the Captain's      in the Chief
12   636   A     lever' shown in the illustration is located __________.   Control Room                               office                Engineer's office      EL-0095

                 A transformer in an electric circuit serves to            generate its own     transform             increase or           convert AC current
                 __________.                                               electrical power     electrical energy     decrease circuit      to DC current
12   637   C
                                                                                                into mechanical       voltage as
                                                                                                energy                required
                 The +5 volt regulated power supply shown in the           115 volt AC bus      Annunciator           +24 volt supply       Annunciator
12   640   C                                                                                                                                                       EL-0094
                 illustration is fed directly from the __________.                              Module                                      Controller
                 As an armature revolves within a magnetic field,          copper loss          eddy-current loss     hysteresis loss       capacitive reaction
                 friction is developed between the rotated magnetized
12   641   C
                 particles as they pass through each magnetization
                 cycle. This results in __________.
                 To test fuses in an energized circuit, you should use a   low voltage light    megohmmeter           voltmeter             resistance meter
12   642   C
                 __________.                                               bulb
                 The main purpose of an electric space heater installed    prevent the          prevent moisture      prevent acidic        keep the lube oil
                 in a large AC generator is to __________.                 windings from        from condensing       pitting of the slip   warm for quick
12   643   B
                                                                           becoming brittle     in the windings       rings                 starting
                                                                                                during shutdown
                 The speed of a squirrel-cage induction motor is           diameter of the      number of stator      rotor winding         rotor conducting
12   644   B
                 determined by the __________.                             stator               poles                 resistance            bars resistance
                 Magnetic controller contacts may become welded            high spring          high ambient          an open coil          low voltage on
12   645   D     together during operating conditions as a result of       pressure             temperature                                 operating coil
                 __________.
                 What are the plant conditions existing in the 'engine     The Bridge is in      The Engine Room The Bridge is in           The Engine Room
                 speed control' diagram shown in the illustration?         control in the 'auto. is in control in the control in the 'auto. is in control in the
12   646   D                                                               maneuver' mode. 'cruise split' mode. split' mode.                'auto. maneuver'       EL-0096
                                                                                                                                            mode.

                 When a transformer is used to step down voltage, the part of the core          the primary coil      not insulated         the secondary coil
12   647   D
                 low voltage winding is __________.
                 How many anodes can the 200 ampere reactor provide One                         Two                   Four                  Six
12   648   C     power to in the circuit shown in the illustration?                                                                                                EL-0090

                 The proper way to mix the electrolyte for a battery is to acid to alkaline     acid to distilled     alkaline water to     distilled water to
12   649   B
                 add __________.                                           water                water                 acid                  acid
                 Which of the referenced wave shapes would appear at A                          B                     C                     D
12   650   A     point "X" of the circuit shown in the illustration?                                                                                               EL-0085




                                                                              48                                                         Electrical Questions-April 2009
Bk   Num   Ans                             Question                                Answer A           Answer B             Answer C             Answer D           Illustr
                 If the illustrated motor fails to start and gives a loud     one of the phases the 'Disc. sw.' is    power to 'L1' at the the control circuit
                 hum when the start button is pushed, the problem is          to the motor is not open                'Disc. sw.' is not   fuse is open
                 __________.                                                  energized                               energized
                                                                              because of an                           because of a
12   651   A                                                                  open motor lead                         problem with the                            EL-0007
                                                                                                                      ship's electrical
                                                                                                                      distribution system

                 Prior to starting an AC generator prime mover, the           manual position     bus neutral         raise voltage        transfer position
12   653   A     voltage regulator selector switch should be placed in                            position            position
                 the __________.
                 A loud buzzing noise at the contacts of a magnetic           weak contact        misalignment of     excessive line       mechanical
12   655   B     controller could indicate __________.                        spring pressure     the magnet faces    current              binding

                 If coils 'R1-R2-R3' at the receiver of figure "B" shown in   Reverse the 60 Hz Interchange leads Interchange leads        Interchange leads
                 the illustration turned opposite of those in the             supply              'S1' and 'R2'.  'S2' and 'R3'.           'R1' and 'R3'.
12   656   D                                                                                                                                                      EL-0092
                 transmitter, what action should be taken to have both        connections to 'S1'
                 turn in the same direction?                                  and 'S2'.
                 An AC circuit has capacitance arranged in series. If the     line frequency      resistance      number of                number of
                 line voltage remains constant, the capacitive reactance                                          commutating poles        interpoles
12   657   A
                 value can be varied by changing the __________.

                 The total voltage of a series circuit is the __________. sum of the              total resistance     sum of the          total current
                                                                          individual voltage      divided by the total individual currents divided by the total
                                                                          drops                   current              multiplied by the   resistance
12   658   A                                                                                                           number of
                                                                                                                       resistors

                 When mixing electrolyte for a lead-acid storage              stirring should   a lead container      always pour the     always pour the
12   659   D     battery, __________.                                         always be avoided should always be      water into the acid acid into the water
                                                                                                used
                 What is the power consumed by 'R2' in the circuit            16 watts          20 watts              24 watts             28 watts
                 illustrated, if the supply is 24 volts and the resistance
12   660   A                                                                                                                                                      EL-0020
                 of R1 is 3 ohms, R2 is 4 ohms, and R3 is 5 ohms?

                 What is the direction of current through the load            Always from point Always from the       It depends on the It cannot be
                 resistor in the circuit shown in the illustration?           "Z" to the        grounded end to       instantaneous     determined
12   661   B                                                                  grounded end.     point "Z".            polarity at point without a                 EL-0085
                                                                                                                      "W".              directional
                                                                                                                                        ammeter.
                 When securing an AC generator, you should FIRST              open the            switch the voltage decrease the field reduce the load on
12   663   D     __________.                                                  generator circuit   regulator to       excitation to      the unit
                                                                              breaker             'manual'           minimum

                                                                                49                                                     Electrical Questions-April 2009
Bk   Num   Ans                         Question                            Answer A                       Answer B           Answer C             Answer D           Illustr
                 The speed of a squirrel-cage motor is usually changed varying the                   adding resistance adding resistance changing the
                 by __________.                                        frequency to the              in series with the in parallel with the number of
12   664   D
                                                                       machine                       stator windings    stator windings      connected poles in
                                                                                                                                             the stator
                 Excessive humming of AC contactors may be caused               burnt arc shields    shorted armature a broken shading high voltage
12   665   C
                 by __________.                                                                      coils              coil
                 Sections "I", "II" and "III" of the circuit shown in the       2, 4 and 6           1, 2 and 3         3, 5 and 8           1, 2 and 6
12   666   D                                                                                                                                                        EL-0093
                 illustration are 'station numbers' __________.
                 Decreasing the frequency in a capacitive circuit while         increase in          decrease in circuit decrease in           decrease in total
12   667   B     maintaining a constant circuit voltage, will result in a/an    apparent power       current             capacitive            impedance
                 __________.                                                                                             reactance
                 How much current will flow in the illustrated circuit if the   2 amps               6 amps              8 amps                10 amps
12   668   A     supply is 24 volts and the resistances of R1 is 3 ohms,                                                                                            EL-0020
                 R2 is 4 ohms, and R3 is 5 ohms?
                 Caution must be exercised during the charging of lead-         the acid will        hydrogen gas is    both plates are        lead peroxide in
                 acid storage batteries as __________.                          become weaker        being continuously changing               the negative plate
12   669   B
                                                                                                     liberated          chemically to lead     is poisonous
                                                                                                                        sulfate
                 What is the total current in the illustrated circuit with a    0.6 amp              1 amp              4 amps                 6 amps
12   670   D     6 volt battery if the resistance of R1 is 2 ohms, R2 is 4                                                                                          EL-0021
                 ohms, and R3 is 4 ohms?
                 When the current flow through a copper wire                    resistance will      insulation will burn temperature will     conductivity will
12   671   C
                 increases, its __________.                                     decrease                                  increase             increase
                 Which of the following actions must be carried out             The fuses must be    The starter must     The three line       Nothing need be
                 before a voltage tester can be used to test the three          removed from the     be placed in the     connections in the   done as long as
                 line fuses to a three-phase motor?                             circuit.             STOP position to motor terminal box       the motor is
12   672   B                                                                                         stop the motor.      must be              running under a
                                                                                                                          disconnected and     light load.
                                                                                                                          tagged.

                 The cycles per second developed by the alternator              the speed of the     the resistance         the synchronous the adjustments
12   673   A     aboard your vessel is determined by __________.                engine driving the   applied to the field   speed of induction made to the
                                                                                alternator           rheostat                                  voltage regulator
                 The counter EMF produced in the windings of a DC               armature has just    armature is not        motor is almost up motor is at rated
12   674   B     motor is 'zero' when the __________.                           begun to turn        turning                to rated speed     speed

                 A loud buzzing noise coming from the contacts in a             excessive current    excessive magnet bouncing of              dirt on magnet
12   675   D     magnetic controller can be caused by __________.                                    gap              contacts                 faces

                 What is the voltage across 'R1' of the illustrated circuit 2 volts                  6 volts                8 volts            10 volts
12   676   B     if the supply is 24 volts and resistance of R1 is 3 ohms,                                                                                          EL-0020
                 R2 is 4 ohms, and R3 is 5 ohms?
                 Component "A" of section "I" shown in the illustration     sealed junction          bell                   buzzer             shunt
12   677   B                                                                                                                                                        EL-0093
                 represents a __________.                                   box
                                                                                  50                                                       Electrical Questions-April 2009
Bk   Num   Ans                             Question                             Answer A             Answer B               Answer C               Answer D           Illustr
                 While testing a semi-conductor diode with an               good                 open                   grounded               shorted
                 ohmmeter, both the forward and reverse readings are
12   678   B
                 almost in the infinity range. This would indicate that the
                 unit is __________.
                 The specific gravity of the electrolyte in a lead-acid     gould plate          titration pipette      hydrometer             litmus paper test
12   679   C
                 battery is measured by a __________.
                 Which of the referenced wave shapes would appear at A                           B                      C                      D
12   680   C     point "Z" in the circuit shown in the illustration?                                                                                                 EL-0085

                 The 'annunciator module' and 'controller' shown in the   blinking lamp on       acknowledging          flashing lamp on       testing the visual
                 illustration together provide for __________.            alarm; testing the     alarm conditions;      alarm; connecting      and audible
                                                                          lamp and alarm;        logging data at the    +24 volts to the       alarms; flashing
                                                                          and logging alarm      end of the watch;      lamp and horn;         lamp on alarm;
12   682   D                                                              conditions             and blinking the       and driving the        and silencing the     EL-0094
                                                                                                 lamp                   horn via a relay       horn when
                                                                                                                                               answering an
                                                                                                                                               alarm
                 The frequency of an AC generator is adjusted by          main alternator        exciter field          prime mover            equalizing reactor
12   683   C
                 means of the __________.                                 field rheostat         rheostat               governor control
                 The function of the commutator in a DC motor is to       allow current flow     reverse the flow of    reduce the             shift the neutral
                 __________.                                              in the armature        current in the field   reluctance of the      running plane of
                                                                          windings under a       poles                  magnetic path          the brushes to
                                                                          given pole to be in                           through the motor      prevent sparking
12   684   A                                                              the same direction
                                                                          at all times



                 Humming or buzzing of electric contacts is a symptom low voltage on the power failure to               a control circuit      a control circuit
12   685   A     of __________.                                       operating coil     the operating coil             ground                 overload

                 The 'pitch controller module' shown in the illustration is 'pitch meter'        'pitch feedback        #5 relay position      pitch error signal
12   686   B     fed the actual pitch position of the propeller from the                         potentiometer'                                                      EL-0095
                 __________.
                 Capacitance in an AC circuit will __________.              stop current flow    allow current flow     oppose any             rectify the current
                                                                            once the capacitor   in only one            change in circuit
12   687   C
                                                                            is fully charged     direction              voltage

                 An ohmmeter used to test for front-to-back resistance    100:1                  500:1                  1000:1                 5000:1
12   688   A     of a PN junction diode should produce roughly what
                 ratio?
                 Which of the following activities occurs during the      The specific        Both plates       Oxygen gas is                  Hydrogen gas is
                 charging process of a lead-acid storage battery?         gravity of the acid change chemically absorbed.                      absorbed.
12   689   A
                                                                          increases.          to lead sulfate.

                                                                             51                                                             Electrical Questions-April 2009
Bk   Num   Ans                           Question                             Answer A         Answer B           Answer C           Answer D                      Illustr
                 As shown in the illustrations, feedback or rudder angle Gyro-compass      Hand steering and Non-follow-up and Gyro-compass
                 repeat-back is used by the steering stand in which      and hand steering non-follow-up only gyro-compass only and synchronizing
12   690   A                                                                                                                                                      EL-0097
                 operational modes?                                      only                                                   only

                 In a simple DC circuit, the resistance is held constant      double               remain the same    be divided by two     be divided by four
12   691   C     while the applied voltage is halved. Current flow,
                 therefore, will __________.
                 When measuring AC current flow, you must always              in series with the in parallel with the insuring correct      using the lowest
                 connect the meter __________.                                power source and power source and polarity                    range possible to
12   692   A                                                                  load               load                                       prevent instrument
                                                                                                                                            damage

                 To increase the frequency of an operating AC                 increase the field   decrease the field increase the          increase the
12   693   D     generator, you should __________.                            excitation           excitation         number of             speed of the prime
                                                                                                                      magnetic poles        mover
                 The counter EMF of a DC motor is maximum when the motor is at rated               armature is not    motor is almost up    armature has just
12   694   A     __________.                                       speed                           turning            to rated speed        begun to turn

                 What is the power consumed by 'R3' in the circuit          12 watts               20 watts           24 watts              48 watts
                 illustrated if the supply is 24 volts and resistance of R1
12   696   B                                                                                                                                                      EL-0020
                 is 3 ohms, R2 is 4 ohms, and R3 is 5 ohms?

                 Which of the following characteristics is most critical in   voltage rating       weight per unit    current rating        inductance per
12   697   C     determining the size of the cable to be used in a                                 length                                   unit length
                 particular circuit?
                 To conduct an in-circuit test of a transistor, you should    voltmeter or         impedance meter  ohmmeter or             wattmeter
12   698   A
                 use a/an __________.                                         transistor tester                     transistor tester
                 The specific gravity of the electrolyte solution in a lead   is not effected      remains the same would read close        gives an indication
                 acid battery __________.                                     during charging      during discharge to 1.830 when           of the state of
12   699   D
                                                                                                                    discharged              charge of the
                                                                                                                                            battery
                 Component "B" of section "I" shown in the illustration       bridge rectifier     selsyn motor       small generator       shielded lamp
12   700   C                                                                                                                                                      EL-0093
                 represents a __________.
                 In the flow of one cycle of single phase AC current past     one time             two times          three times           four times
12   701   B     any given point in a circuit, the maximum current peak
                 occurs __________.
                 If coil 'R1-R2' at the receiver of figure "A" shown in the   No action is         Reverse the 60 Hz Interchange            Interchange
                 illustration were in 180 degree error with respect to that   necessary as this    supply              connections 'S1'     connections 'S1'
12   702   B                                                                                                                                                      EL-0092
                 of the transmitter, what corrective action should be         is proper            connections at 'R1' and 'S2'.            and 'S3'.
                 taken?                                                       operation.           and 'R2'.



                                                                                 52                                                      Electrical Questions-April 2009
Bk   Num   Ans                       Question                                  Answer A              Answer B              Answer C          Answer D              Illustr
                 AC and DC generators are similar in that they            both initially        both rectify the      are constructed at both supply three-
                 __________.                                              generate              voltage before        the same physical phase power
12   703   A                                                              alternating           delivery              size for the same
                                                                          voltages                                    kilowatt rating

                 Shunt, series, and compound wound motors, are all        constant potential, variable potential, variable potential, constant potential,
                 DC motors designed to operate from __________.           variable current    constant current    variable current    constant current
12   704   A
                                                                          DC sources          DC sources          DC sources          DC sources

                 Motor starter or controller contacts may become          open too quickly      close under           open or close too     close under
12   705   D     welded together if the contacts __________.              and arc               excessive             quickly               excessive starting
                                                                                                pressure                                    current
                 Which of the referenced wave shapes would appear at A                          B                     C                     D
12   706   D     point "Y" in the circuit shown in the illustration?                                                                                              EL-0085

                 Which of the following statements concerning copper      Number 12 AWG         Number 12 AWG         Number 10 AWG         Number 12 AWG
                 wire sized by AWG numbers is correct?                    wire has a higher     wire at 25°C has      wire has a higher     wire is larger than
                                                                          current rating than   more resistance       dielectric strength   number 10 AWG
12   707   B                                                              10 AWG wire.          per 1000 ft than      than 12 AWG wire.     wire.
                                                                                                10 AWG wire at
                                                                                                25°C.
                 Normally, the FIRST step in troubleshooting a            carefully remove      give the circuit an   test for continuity visually inspect the
                 transistor circuit card is to __________.                the transistors       initial test with a   with a low voltage card
12   708   D
                                                                          from the card         signal generator      DC supply

                 During discharge of a lead-acid storage battery, which The acid becomes Both plates       The acid becomes Hydrogen gas is
                 of the following actions occurs?                       stronger.        change chemically weaker.          liberated.
12   709   C                                                                             to ammonium
                                                                                         chloride.

                 An open-circuit fault between the pressure switch and 3.5 volts were           'reduction gear       50 PSI were         the pressure
                 the 'annunciator module' shown in the illustration would applied to the 'set   lube oil pressure'    applied to the 'set switch closed
12   710   B     cause the alarm circuit to react in the same manner as point module'           fell below switch     point module'                               EL-0094
                 if __________.                                                                 setting

                 If the length of a wire is halved and the cross-sectional quartered            unchanged             doubled               quadrupled
12   711   A     area is doubled, the resistance will be __________.

                 Prior to taking a resistance reading with a volt-ohm-    an improper           weak batteries        a faulty zero ohms a faulty meter
                 milliammeter, the 'zero' setting must be adjusted. After resistance range                            knob               movement
                 clipping the two leads together, you find the adjustment setting
12   712   B     knob will not return the pointer to 'zero'. This is most
                 likely an indication of __________.

                                                                             53                                                       Electrical Questions-April 2009
Bk   Num   Ans                          Question                                 Answer A           Answer B               Answer C              Answer D            Illustr
                 Which of the following devices are protected from          Alternators          Wave guides           Exciters               Amplidynes
12   713   A
                 being motorized by a reverse-power relay?
                 An advantage of DC motors over AC motors is that           are less expensive require less            can be started         offer a more
                 they __________.                                                              maintenance             across the line        effective means of
12   714   D
                                                                                                                                              controlling speed

                 If many turns of an alternating current coil for a     temperature will         will probably burn    will continue to       will operate on
12   715   B     contactor become short circuited, the coil __________. drop                     out immediately       operate                reduced current

                 As shown in the illustration, when the 'speed control'     Relays #1, #5 and the 'slew rated          the RPM 'function      the 'E/P
                 system is in 'SPLIT' __________.                           #8 are not used   controller' is           generator' and         converters' are
                                                                                              grounded through         'thrust levers' have   bypassed and air
12   716   C                                                                                  Relay #6                 no control             is fed directly to    EL-0096
                                                                                                                                              the governors via
                                                                                                                                              the 'load sharing
                                                                                                                                              valve'
                 Which of the wave forms shown in the illustration will     A                    B                     C                      D
12   718   B                                                                                                                                                        EL-0064
                 be produced when the circuit is in use?
                 Relative to the secondary winding of a step-up             more turns           fewer turns           same number of         twice as many
12   721   B     transformer, the primary winding will have                                                            turns but smaller      turns
                 __________.                                                                                           wires
                 Before using a volt-ohmmeter to measure resistance         replace all          test the insulation   make sure the test     hold the leads
                 readings, you should __________.                           batteries            resistance of the     leads do not touch     together and 'zero'
12   722   D
                                                                                                 leads                                        the meter

                 To equalize the power factor of two alternators         field excitation of     governors of both phase sequence is kilowatt load is
12   723   A     operating in parallel, the __________.                  both units is           units are adjusted altered          evenly divided
                                                                         adjusted
                 Which of the following operating characteristics for DC series                  shunt                 cumulative-            differential-
12   724   A     motors is considered to give high starting torque?                                                    compound               compound

                 If a magnetic controller contactor fails to pick up when   overload             misalignment of    low spring                an open contactor
                 the coil voltage is applied to the contactor coil, the                          the affected       pressure                  coil
12   725   D
                 cause may be __________.                                                        contactor contacts

                 The total power used up in a series circuit is             the sum of the       the sum of the        always less than never more than
                 __________.                                                powers used in       powers used in        the power used in the power used in
                                                                            each load            each load             the smallest load largest load
12   726   B                                                                (resistor) divided
                                                                            by the number of
                                                                            loads
                 When the operating handle of a molded-case circuit         on                   off                   reset                  tripped
12   727   D     breaker is in the mid-position, this indicates that the
                 circuit breaker is __________.
                                                                                 54                                                       Electrical Questions-April 2009
Bk   Num   Ans                           Question                                  Answer A              Answer B              Answer C               Answer D          Illustr
                 As shown in the illustration, which of the symbols is        A                      B                     C                     D
12   728   B                                                                                                                                                           EL-0066
                 used to represent a capacitor?
                 When you check the specific gravity of the battery           the battery is fully   any water that has    a hydrometer          temperature has
                 electrolyte with a hydrometer, it should be kept in mind     charged when the       been previously       reading is            no effect on
                 that __________.                                             indicator floats low   added to the cells    inaccurate if taken   hydrometer
12   729   C                                                                  in the electrolyte     will dilute the       immediately after     readings
                                                                                                     solution and give a   water is added to
                                                                                                     false reading         the cell

                 As shown in the illustration, a 'pitch cutback' feature is   pitch error of any  wrong direction of excessive                   only one engine
                 incorporated in the system. This circuit reduces pitch       magnitude           the 'pitch servo'  propeller speed or          on the line
12   730   C                                                                                                                                                           EL-0095
                 amount to prevent engine overload when it senses                                                    fuel to either
                 __________.                                                                                         engine
                 The total resistance of a parallel circuit is always         larger than that of smaller than that equal to the sum             equal to the sum
                 __________.                                                  the branch with     of the branch with of the individual           of the individual
                                                                              the greatest        the lowest         branch resistances          branch resistances
12   731   B                                                                  resistance          resistance                                     divided by the
                                                                                                                                                 number of
                                                                                                                                                 branches

                 What is the current flowing through R1 of the illustrated 0.5 amps                  1.5 amps              3.0 amps              6 amps
                 circuit with a 6 VDC battery if the resistance of R1 is 2
12   732   C                                                                                                                                                           EL-0021
                 ohms, R2 is 4 ohms and R3 is 4 ohms?

                 Equal power factors on paralleled AC generators are          voltage regulator      reverse power         reverse current       governor control
12   733   A
                 maintained by an automatic __________.                                              relay                 relay                 switch
                 If a magnetic controller contact fails to pick up when       low spring             low voltage to the    the residual          dirty contact faces
12   735   B     the operating coil is energized, one possible cause          pressure               coil                  magnetism of the
                 may be __________.                                                                                        contact faces
                 Component "D" in section "I" shown in the illustration       selector switch        vibrating reed        junction box          ring counter
12   736   A                                                                                                                                                           EL-0093
                 represents a __________.                                                            indicator
                 In the electrical schematic, a Zener diode will be           A                      B                     C                     D
12   738   A     represented by which of the symbols shown in the                                                                                                      EL-0067
                 illustration?
                 Which of the listed forms of water should be added to        saltwater              brackish water        distilled water       light water
12   739   C
                 a lead-acid battery?
                 What is the voltage across 'R2' of the illustrated circuit   2 volts                6 volts               8 volts               10 volts
                 if the supply is 24 volts and the resistance of R1 is 3
12   740   C                                                                                                                                                           EL-0020
                 ohms, R2 is 4 ohms, and R3 is 5 ohms?

                 If the resistance of a circuit is cut in half and the      doubled                  quadrupled            unchanged             cut in half
12   741   A     applied voltage is kept constant, the current flow will be
                 __________.

                                                                                  55                                                         Electrical Questions-April 2009
Bk   Num   Ans                             Question                             Answer A             Answer B            Answer C              Answer D           Illustr
                 What is the current flow through R1 of the circuit         2 amps               4 amps              6 amps                12 amps
12   742   C     illustrated if the resistance of R1 is 2 ohms, R2 is 3                                                                                          EL-0021
                 ohms and R3 is 6 ohms with a 12 VDC battery?
                 The power factor at which a paralleled AC generator        connected load       prime mover         field excitation      generator's rated
12   743   C     operates is usually adjusted by the __________.                                 speed                                     voltage

                 Which of the listed types of motor controllers and         Across-the-line      Primary-resistor    Autotransformer       Part-winding
12   745   C                                                                                                                                                     EL-0080
                 starters is illustrated?
                 What would be the total current flowing in the circuit     1 amp                2 amps              5 amps                15 amps
                 shown in the illustration if the source is 30 volts, the
12   747   B                                                                                                                                                     EL-0032
                 resistance of R1 is 10 ohms, R2 is 10 ohms and R3 is
                 10 ohms?
                 As shown in the illustration, which of the elements        Base                 Emitter             Cathode               Collector
12   748   D     listed does the line "B" represent in the basic                                                                                                 EL-0068
                 schematic symbol of a PNP transistor?
                 Which of the processes listed occurs during the            Negative plates      Positive plates     Both plates           Both plates
12   749   B     charging of a lead-acid storage battery?                   change to lead       change to lead      change to lead        change to lead
                                                                            peroxide.            peroxide.           peroxide.             sulfate.
                 What type of service is NOT provided by the circuit        Logging of engine    Printed record of   Visual metering of    Periodic recording
                 shown in the illustration?                                 order signals from   alarms as they      temperature and       of pressure and
12   750   A                                                                the bridge.          occur.              pressure              temperature           EL-0094
                                                                                                                     conditions.           conditions.

                 The primary function of an electric motor is to            develop torque       generate high       produce a            generate high
12   751   A     __________.                                                                     voltages            magnetic field       electrical
                                                                                                                                          resistance
                 Current measuring instruments must always be               series with a        parallel with a     series-parallel with delta with the
12   752   A
                 connected in __________.                                   circuit              circuit             a circuit            shunt
                 If the excitation is increased to one of two alternators   power factor will    power factor will   kilowatt load will   ampere load will
12   753   A     operating in parallel, the __________.                     change in the        change in the       be greatly           be greatly
                                                                            lagging direction    leading direction   increased            decreased
                 In a series wound motor, the current passing through       armature             shunt field         reactance            laminations
12   754   A     the field windings is also passing through the                                                      comparator
                 __________.
                 As shown in the illustration, 'H1' and 'H2' are            fixed capacitors     variable capacitors contacts, closed      contacts, open
12   755   D     __________.                                                                                         when the circuit is   when the circuit is   EL-0058
                                                                                                                     energized             energized
                 Which of the listed devices may be installed on a large Temperature             A CO2 fire          Electric space        All of the above.
                 diesel-electric alternating current propulsion          detector coils          extinguishing       heaters to prevent
                 generator?                                              inserted in the         system.             condensation of
12   756   D                                                             stator slots for                            moisture.
                                                                         measuring stator
                                                                         temperature.

                                                                              56                                                        Electrical Questions-April 2009
Bk   Num   Ans                           Question                             Answer A               Answer B            Answer C             Answer D           Illustr
                 What would be the voltage drop across the parallel       5 volts                10 volts            20 volts             30 volts
                 branches of the circuit shown in the illustration if the
12   757   B     source is 30 volts the resistance for R1 is 10 ohms, R2                                                                                        EL-0032
                 is 10 ohms and R3 is 10 ohms?

                 As shown in the illustration, which electrical symbol      A                    B                   C                    D
12   758   C                                                                                                                                                    EL-0065
                 represents a PNP type semiconductor?
                 Power necessary to operate the horn "relay" shown in       comes from each      is supplied from a is conducted          also lights lamps
12   759   A     the illustration __________.                               station's magneto    115 volt source    through the relay's   "R" and "T"           EL-0093
                                                                                                                    contacts
                 The total power consumed in a parallel circuit is          the sum of the       always less than the sum of the          never more than
                 __________.                                                powers used in       the power used in powers used in         the power used in
                                                                            each load            the smallest load each individual        the largest load
12   760   C                                                                (resistor) divided                      load
                                                                            by the number of
                                                                            loads
                 The resistance of electric wire will decrease as its       length increases     cross-sectional     temperature          percent of metallic
12   761   B     __________.                                                                     area increases      increases            purities increases

                 Which of the instruments listed is generally connected Ammeter                  Megohmmeter         Wattmeter            Voltmeter
12   762   A
                 in series in the circuit?
                 The speed of a series wound winch motor is controlled varying the voltage       the weight of the   overcurrent        a hydraulic speed-
                 by __________.                                         applied to the           load on the cargo   protection devices limiting governor
12   764   A
                                                                        motor                    boom                in the motor

                 A-1', as shown in the illustration, describes a            normally-closed      double pole knife   normally-open        single pole knife
12   765   A     __________.                                                overload relay       switch              overload relay       switch                EL-0017
                                                                            contact                                  contact
                 What is the voltage across 'R3' of the illustrated circuit 2 volts              6 volts             8 volts              10 volts
                 if the supply is 24 volts and the resistance of R1 is 3
12   766   D                                                                                                                                                    EL-0020
                 ohms, R2 is 4 ohms, and R3 is 5 ohms?

                 The arc resulting from the tripping of a circuit breaker   designing the        directing the arc   an inverse timed     instantaneous
                 is prevented from damaging the contacts by                 contacts to open     into an arc chute   thermal trip for     magnetic trip for
12   767   B
                 __________.                                                slowly                                   short circuit        overload currents
                                                                                                                     currents
                 Which of the devices listed is indicated by the symbols Diodes                  Linear inductors    Capacitors           Transistors
12   768   A     lettered "A" to "F", shown in the illustration?                                                                                                EL-0016

                 When a lead-acid battery begins gassing freely while be increased               remain unchanged be decreased            shut off
12   769   C     receiving a normal charge, the charging current should
                 __________.

                                                                                57                                                    Electrical Questions-April 2009
Bk   Num   Ans                           Question                             Answer A               Answer B           Answer C          Answer D                Illustr
                 When the voltage remains constant and the resistance    increases by the       increases            remains the same decreases
12   771   D     is increased in a series circuit, the flow of current   square of the
                 __________.                                             original value
                 An ammeter should be used to measure __________.        the voltage            circuit continuity   current flow in a    total or partial
12   772   C                                                             between two                                 circuit              circuit resistance
                                                                         points in a circuit
                 Why is it desirable to operate paralleled AC generators Circulating            Field excitation   Generator rotors       Because a power
                 at the same power factor?                               currents are kept      losses are kept to will have a lesser     factor increase will
12   773   A                                                             to a minimum.          a minimum.         tendency to hunt.      decrease kilowatt
                                                                                                                                          output.

                 As shown in the illustration, "S" is the __________.      safety switch        overload trip        start button         stop button
12   775   D                                                                                                                                                     EL-0017
                 What would be the voltage drop across the series         5 volts               10 volts             20 volts             30 volts
                 resistor of the circuit shown in the illustration if the
12   776   C                                                                                                                                                     EL-0032
                 source is 30 volts, the resistance of R1 is 10 ohms, R2
                 is 10 ohms and R3 is 10 ohms?
                 In the pitch control diagram shown in the illustration,  One engine is on      One engine is on     Both engines are     Both engines are
                 what are the present plant operating conditions?         the line, cruise      the line,            on line, cruise      on line,
                                                                          mode is selected      maneuvering          mode is selected     maneuvering
12   777   D                                                              and the engine        mode is selected     and the bridge is    mode is selected       EL-0095
                                                                          room is in control.   and the bridge is    in control.          and the engine
                                                                                                in control.                               room is in control.

                 The schematic diagram shown in the illustration           Bridge rectifier     Magnetic amplifier Flip-flop generator Cathodic amplifier
12   778   A                                                                                                                                                     EL-0069
                 represents which of the listed solid-state circuits?
                 The charge of a lead-acid battery is checked with a       manometer            hydrometer           viscosimeter         ohmmeter
12   779   B
                 __________.
                 What is the current through R2 of the circuit illustrated 0.5 amp              1.5 amps             3.0 amps             6 amps
                 if the resistances of R1 is 2 ohms, R2 is 4 ohms, and
12   780   B                                                                                                                                                     EL-0021
                 R3 is 4 ohms with a 6 volt battery?

                 When the voltage remains constant, and the                decreases            remains the same increases                increases by the
12   781   A     resistance increases in a series circuit, current flow                                                                   square
                 __________.
                 A DC ammeter is always connected __________.              in series with a     in parallel with a   with internal        without regard to
12   782   A
                                                                           circuit              circuit              shunts only          polarity
                 The voltage output of an AC generator is accurately       changing the         varying the          varying the DC       shorting out part of
                 controlled by __________.                                 sensitivity of the   reluctance of the    exciter voltage      the armature
12   783   C                                                               prime mover to       air gap                                   windings
                                                                           large changes in
                                                                           voltage

                                                                              58                                                       Electrical Questions-April 2009
Bk   Num   Ans                           Question                              Answer A               Answer B             Answer C               Answer D          Illustr
                 As shown in the illustrations, which statement           The rudder            The rudder            The rudder             The rudder
                 characterizes steering operations using the 'non-follow- responds while the    responds while the    responds to the        responds to the
                 up controller'?                                          switch is held left   switch is held left   gyro input if the      Wheel if the switch
                                                                          or right and          or right and halts    switch is held left    is held left and
                                                                          returns to mid-       in its present        and responds to        responds to the
                                                                          ships when the        position when the     the Wheel if the       gyro input if the
12   786   B                                                              self-centering        self-centering        switch is held         switch is held        EL-0098
                                                                          switch is released.   switch is released.   right; in both         right; in both
                                                                                                                      cases, it returns to   cases, it remains
                                                                                                                      mid-ships with         in position when
                                                                                                                      switch 'off'.          switch is 'off'.



                 You can determine if a circuit breaker has tripped by    examining the         checking for which looking for a             all of the above
                 __________.                                              position of the       of the breakers is burned-out link
12   787   A
                                                                          handle                warm

                 An operational amplifier, as used in today's consoles,   1 volt, the output    5 volts, the output 5 volts, the output 10 volts, the
                 may have a calculated gain of 5. This means that as      changes 5 volts       changes 1 volt      changes 10 volts output changes 5
12   788   A
                 the input changes by __________.                                                                                       volts

                 Component "C" in section "I" shown in the illustration   a selectable          a 'fuse blown'      'reset' and 'trouble' a handset with
12   789   D     represent __________.                                    holding coil          indicator circuit   lamps                 switch and voice         EL-0093
                                                                          arrangement                                                     elements
                 Under which of the following conditions will a lead-acid To determine its      Whenever a cell     When one or more All of the above.
                 battery be given a 'test discharge'?                     capacity.             cannot be brought cells is found to
                                                                                                within 10 points of have less than
12   790   D                                                                                    full charge         normal voltage
                                                                                                specific gravity.   after an equalizing
                                                                                                                    charge.

                 Which of the formulas listed is correct for determining P = (E)(E)/R           P = (I)(R)(R)         P = (I)(I)/R           P = E/R
12   791   A
                 power?
                 Which of the listed meters uses a shunt connected in Voltmeter                 Power factor meter Ammeter                   Wattmeter
12   792   C     series with the load, but parallel with the meter
                 movement?
                 What is the current flowing through R2 of the illustrated 2 amps               4 amps                6 amps                 12 amps
                 circuit if the voltage is 12 VDC and the resistance of
12   793   B                                                                                                                                                       EL-0021
                 R1 is 2 ohms, R2 is 3 ohms and R3 is 6 ohms?




                                                                            59                                                        Electrical Questions-April 2009
Bk   Num   Ans                            Question                                   Answer A           Answer B              Answer C           Answer D           Illustr
                 Which of the following statements describes what will          The motor will not The direction of      The direction of    The field pole
                 happen when both the polarity of the field poles, and          start.             rotation of the       rotation of the     windings will
12   794   C     the direction of current to the brushes of a DC motor                             armature will be      armature will       become
                 are reversed?                                                                     reversed.             remain the same.    overheated.

                 A slow continual loss of electrolyte level from one cell       a cracked casing   too low a charging the specific gravity one filler cap
                 of a storage battery could be due to __________.                                  rate               being higher than installed too tightly
12   795   A
                                                                                                                      normal

                 Nickel-cadmium batteries are superior to lead-acid             deliver a large    need fewer cells in   have higher output all of the above
                 batteries at high discharge rates because they                 amount of power    connected series      voltages and
12   796   A     __________.                                                    and can be         and less mounting     require no
                                                                                recharged in a     space                 maintenance
                                                                                shorter time
                 When the operating handle of a molded-case circuit             in the 'closed'    in the 'opened'       tripped             reset
12   797   C     breaker is in the mid-position, the circuit breaker is         position           position
                 indicated as being __________.
                 When a console indicating lamp burns out, attempts to the new lamp may            removing a faulty     attention should    a socket/wiring
                 renew it should not be made while maneuvering          be of a higher             lamp usually          be paid only to     fault may cause a
                 because __________.                                    wattage and cause          causes an alarm       engine orders       ground or short
12   798   D                                                            heat damage to             to sound on the                           circuit to shut
                                                                        the lens                   bridge                                    down a vital
                                                                                                                                             function
                 The sensor connected to 'signal conditioner'                   thermocouple       transducer            inverter            RTD
12   800   D     (6000F085) shown in the illustration is a/an                                                                                                      EL-0094
                 __________.
                 The rate at which heat is produced in a direct current         P divided by R     I squared times R E divided by I          I times R divided
12   801   B
                 circuit is equal to __________.                                                                                             by T
                 If Relay #5 changed contact position grounding the             pitch feedback     Engine room           Engine room         Bridge thrust lever
                 'auto' input to the 'pitch controller module', pitch control   potentiometer      thrust split          thrust lever only   only
12   803   B                                                                                                                                                       EL-0095
                 would be effected by the __________.                                              potentiometer

                 What would be the total power consumed in the circuit 10 watts               40 watts            45 watts           60 watts
                 shown in the illustration if the source is 30 volts the
12   805   D                                                                                                                                                       EL-0032
                 resistance for R1 is 10 ohms, R2 is 10 ohms, and R3 is
                 10 ohms?
                 The ring circuit of the system shown in the illustration either terminal "T" either terminal "B" both terminals "B" both terminals "T"
12   806   C     would become inoperative if a ground developed at        or "C"              or "R"              and "C"            and "R"                       EL-0093
                 __________.



                                                                                  60                                                     Electrical Questions-April 2009
Bk   Num   Ans                          Question                               Answer A             Answer B              Answer C             Answer D            Illustr
                 Which of the following represents a characteristic of an Accidental contact   Double ground          Ground detection     Accidental contact
                 ungrounded electrical distribution system?               between one line     faults on different    systems are          between one line
                                                                          and ground does      phases will not        unnecessary.         and ground will
12   807   A                                                              not cause an         cause an outage.                            always cause an
                                                                          outage.                                                          outage.

                 As shown in the illustrations, ordered rudder angle is   power unit to the steering gear to          magnetic amplifier   rudder yoke to the
12   808   A     fed back from the __________.                            magnetic amplifier the control              to the steering      non-follow-up          EL-0097
                                                                                             potentiometer            gear                 controller
                 What is the approximate voltage per cell produced by     0.85 volts         1.35 volts               2.20 volts           6.05 volts
12   809   B
                 the nickel-iron (Edison) battery?
12   811   C     One horsepower is equal to __________.                   500 watts            663 watts            746 watts             1,000 watts
                 An ammeter reads slightly above 'zero' when its leads    mechanical           a poor ground for    static electricity in resistors inside the
12   812   A     are disconnected, this is a result of __________.        misalignment of      the meter case       the air               meter storing
                                                                          the meter pointer                                               charges
                 When an alternator is to remain idle for even a few      lift the brushes     insulate the         energize the          open the
                 days __________.                                         and disconnect the   collector rings with heater circuit        equalizing bus
12   813   C
                                                                          pigtails             strips of cardboard                        disconnect switch

                 Proper storage battery maintenance includes              keeping              making sure            insulating the       maintaining a high
                 __________.                                              connections tight    electrolyte level is   terminals with       charging rate at all
12   814   A
                                                                          and casing           below the              naval jelly          times
                                                                          surfaces clean       separator plates
                 Part of the insulation of practically all electrical     asbestos             water                  fiber                plastic
12   816   B     machinery is in the form of organic compounds which
                 contain some amount of __________.
                 When the current in a power transmission line is         increases as the     decreases as the remains the same,          increases in direct
                 increased, the power loss __________.                    square of the        square root of the as it is                 proportion as the
12   817   A
                                                                          current              current            independent of           current
                                                                                                                  current flow
                 Modern handheld non-contact digital tachometers          the vibrating tach   the coupling bolts a small bulb             a piece of
                 operate by counting light pulses returned to the unit by generator                               attached to the          reflective tape
12   818   D
                 __________.                                                                                      shaft                    mounted on the
                                                                                                                                           rotating shaft
                 To determine the state of charge of a nickel-cadmium     voltmeter            hydrometer             ammeter              potentiometer
12   819   A     battery, you would use a/an __________.

                 The true power indicated by the pointer movement of a power factor of the angle of coil              inertia of the       high resistance
                 wattmeter depends on the current flow through the     load                displacement               movable coil         from the load
12   821   A
                 load, the magnitude of the potential across the load,
                 and the __________.


                                                                             61                                                        Electrical Questions-April 2009
Bk   Num   Ans                       Question                                  Answer A               Answer B              Answer C               Answer D         Illustr
                 The shunt of a DC ammeter should be connected in         series with the        parallel with the     parallel with the      series with the
                 __________.                                              load and in parallel   load and in series    load and in parallel   load and in series
12   822   A
                                                                          with the meter         with the meter        with the meter         with the meter
                                                                          movement               movement              movement               movement
                 The standard method of controlling the output voltage prime mover               number of poles       alternator field       load on the
12   823   C     of a 440 volt, 60 Hz, AC generator is accomplished by speed droop                                     excitation             alternator
                 adjusting the __________.
                 Common nickel-cadmium and nickel-iron storage            acid primary cells     alkaline primary      acid secondary         alkaline secondary
12   826   D
                 batteries utilize __________.                                                   cells                 cells                  cells
                 Due to the operating characteristics of the system, time main lighting          motor starting        emergency lighting     general alarm
12   827   B     lag fuses (or dual-element fuses) are necessary for      circuits               circuit               circuits               circuits
                 use in __________.
                 Loss of residual magnetism in an alternator or           running the rotor in   allowing the          running the            using a storage
                 generator can be corrected for by __________.            the opposite           generator to run at   generator at           battery or battery
                                                                          direction for 5        10% of normal         normal speed with      charger to 'flash'
12   828   D                                                              minutes                speed for 5           the field rheostat     the field
                                                                                                 minutes               fully
                                                                                                                       counterclockwise

                 What is the current flowing through R3 of the illustrated 2 amps                4 amps                6 amps                 12 amps
                 circuit if the battery is 12 VDC and resistance of R1 is
12   829   A                                                                                                                                                       EL-0021
                 2 ohms, R2 is 3 ohms, and R3 is 6 ohms?

                 The sensor connected to 'signal conditioner'              thermocouple          transducer            inverter               RTD
12   830   A     (6000AH170) shown in the illustration is a/an                                                                                                     EL-0094
                 __________.
                 An accidental path of low resistance which passes an      polarized ground      short circuit         ground reference       open circuit
12   831   B     abnormal amount of current is known as a/an                                                           point
                 __________.
                 A milliammeter, with a full scale deflection reading of   9.8 and 10.0          9.8 and 10.2          8.0 and 12.0           8.0 and 10.0
                 100 milliamps, is known to have an accuracy of plus or    milliamperes          milliamperes          milliamperes           milliamperes
12   832   B     minus 2%. A meter reading of 10 milliamps would
                 indicate a line current of between __________.

                 Which of the following materials is a good electrical     wood                  silver                copper                 gold
12   834   A
                 insulator?
                 Cleaning of electrical insulation should be               done every six        accomplished          determined by          performed
                 __________.                                               months                every 12 months       need and not the       whenever the
12   835   C
                                                                                                                       calendar               electrician is not
                                                                                                                                              otherwise busy
                 The plates of a wet cell NiCad storage battery are        potassium             lead and lead         silver oxide and       combinations of
                 made of __________.                                       hydroxide with a      peroxide              lead sulfate           nickel plus
12   836   D
                                                                           small amount of                                                    cadmium salts
                                                                           sulfuric acid
                                                                             62                                                           Electrical Questions-April 2009
Bk   Num   Ans                          Question                                Answer A              Answer B              Answer C            Answer D               Illustr
                 An "instantaneous-trip" type fuse will __________.        open as soon as       allow a preset         open a circuit by  reset itself when
                                                                           the load current      delay between          using a time delay the overcurrent is
12   837   A                                                               exceeds its set       overcurrent and        element with a     corrected
                                                                           point                 melting                magnetic trip

                 Basic electrical motor action depends on __________. a conductor                a current carrying the relative force the relative force
                                                                      rotated within a           conductor placed of the commutator of the armature
12   838   B                                                          magnetic field             in a magnetic field and commutating and interpoles
                                                                                                                     poles

                 When mixing electrolyte, which of the following              Add the acid to the Use a heavy duty      Add the water to       Mix the solution
12   839   A
                 precautions should always be observed?                       water.              aluminum pail.        the acid.              outdoors.
                 What power would be consumed in EACH of the                  5 watts             10 watts              20 watts               40 watts
                 branch resistors of the circuit shown in the illustration if
12   840   B     the source is 30 volts, the resistance for R1 is 10                                                                                                  EL-0032
                 ohms, R2 is 10 ohms and R3 is 10 ohms?

                 Which of the following statements about copper wire       Number 12 AWG         Number 10 AWG          Number 12 AWG          Number 12 AWG
                 sized by the AWG rating is correct?                       wire has a higher     wire has a higher      wire is larger than    wire at 25°C has
                                                                           current rating than   dielectric strength    Number 10 AWG          more resistance
12   841   D                                                               number 10 AWG         than number 12         wire.                  per 1000 feet than
                                                                           wire.                 AWG wire.                                     No. 10 AWG wire
                                                                                                                                               at 25°C.
                 Which of the following statements represents the     In series with the         In series with the     In parallel with the   In parallel with the
                 correct method of connecting the shunt of an ammeter load and in series         load and in parallel   load and in series     load and in parallel
12   842   B     prior to taking a reading?                           with the meter             with the meter         with the meter         with the meter
                                                                      movement.                  movement.              movement.              movement.

                 Relative to the direction of rotation, a D.C. motor       main pole             interpole following main pole                 interpole
12   843   C     commutating pole has the same polarity as the             following                                 preceding                 preceding
                 __________.
                 One method of troubleshooting digital circuits in a       supply alternate    ground all inputs open all inputs and           vary each input
                 console is to __________.                                 logic levels at the and test for a logic test for a logic '0'       smoothly from 0-
                                                                           input(s) and test   "1" at the output    at the output              10 volts and test
12   844   A                                                               for change of                                                       for similar variance
                                                                           state conditions at                                                 at the output
                                                                           the output

                 Propeller pitch can be controlled by either the 'bridge   #1                    #2                     #3                     #4
                 or engine room thrust lever' shown in the illustration;
12   845   D     but only with one engine on the line whether in 'cruise                                                                                              EL-0095
                 or maneuver' mode. The cause is most likely a faulty
                 relay __________.

                                                                                63                                                       Electrical Questions-April 2009
Bk   Num   Ans                          Question                                Answer A             Answer B              Answer C            Answer D             Illustr
                 Upon failure of the normal power supply, the               main bus tie         automatic bus        line connection      power failure
12   847   B     emergency generator is placed on the line by the           feeder               transfer device      feeder               alarm bus
                 __________.
                 Routine maintenance of a ship's service alternator         changing the         megger testing of    lubricating          periodic cleaning
                 should include __________.                                 pedestal bearing     all rectifying       excitation slip      of the air filters or
12   848   D
                                                                            insulation yearly    diodes               rings                screens

                 The sensor connected to 'signal conditioner'           thermocouple             transducer           inverter             RTD
12   849   B     (6000F125) shown in the illustration is a/an                                                                                                      EL-0094
                 __________.
                 Nickel-cadmium storage batteries are superior to lead- put out higher           can remain idle      need fewer cells in all of the above
                 acid batteries because they __________.                voltages and             and keep a full      series and use
12   850   B
                                                                        require no               charge for a long    less mounting
                                                                        maintenance              time                 space
                 Which of the following meters uses a shunt connected voltmeter                  power factor meter   wattmeter           ammeter
12   852   D     in series with the load, but parallel with the meter
                 movement?
                 Electrical machinery insulation will break down more   low loading of           frequent megger      high temperatures high operating
12   853   C     rapidly due to __________.                             motors and               testing              and vibration     frequencies
                                                                        generators
                 The speed of a multi-speed, squirrel-cage, induction   reconnecting             changing the RPM changing the             reconnecting the
                 motor operating in a fixed frequency system can be     stator windings for      of the rotor flux phase sequence          stator so that no
12   854   A     changed by __________.                                 different numbers                          of the applied          poles have the
                                                                        of poles                                   voltage                 same polarity

                 In the construction of D.C. motors, parts of both the opposite main pole rotor core                  interpole            same main pole
12   855   D     series and shunt fields are wound on the __________.

                 A handheld reflective digital tachometer could give a                     partially aimed at a
                                                                            aimed directly at                         positioned 5-10      the tape is too
12   856   B     false reading if __________.                                              60 Hz. fluorescent
                                                                            the rotating shaft                        inches from the      shiny
                                                                                           light                      rotating shaft
                 Which of the listed sections of an emergency            The generator and The 450 volt, 60           The 120 volt, 3      The 24 volt DC
12   857   D     switchboard is used to supply power for alarm signals bus transfer        cycle, 3 phase bus         phase, 60 cycle      bus
                 under emergency conditions?                             section                                      bus
                 As shown in the illustration, the M-G set's three-phase motor and the     motor and the              generator and the    main field and the
12   858   C     motor drives the __________.                            generator         exciter                    exciter              interpole field         EL-0101

                 Which of the listed ranges represents the specific         1.100 to 1.150       1.180 to 1.200       1.280 to 1.300       1.750 to 2.000
12   859   C     gravity for the electrolyte of a fully charged lead-acid
                 battery at room temperature?


                                                                              64                                                        Electrical Questions-April 2009
Bk   Num   Ans                         Question                                  Answer A           Answer B             Answer C              Answer D            Illustr
                 Inductance is the property of an electric circuit that      opposes any        opposes any         aids any changes      aids any changes
                 __________.                                                 change in the      change in the       in the applied        in the current
12   861   B                                                                 applied voltage    current flow        voltage               through the circuit
                                                                                                through the circuit

                 An important factor in reducing D.C. motor commutator keeping the        ensuring a very           establishing the      all of the above
                 wear is __________.                                   ambient humidity low brush current           copper oxide
12   862   C
                                                                       as low as possible density                   surface film

                 When removing ball or roller bearings from the shaft of rawhide hammer         brass mallet        wheel puller          soft iron pry bar
12   863   C
                 a motor, you should use a __________.
                 The rotation of a three-phase induction motor can be    interchanging any      disconnecting one switching the           permanently
                 reversed by __________.                                 two of the three       of the three line   shunt field coil      disconnecting any
12   864   A                                                             line leads to the      leads to the stator leads                 two of the three
                                                                         stator                                                           line leads to the
                                                                                                                                          stator
                 The 'safe switch' of the winch controller shown in the      through the master when heater circuit by contactor coil     manually by the
12   865   D     illustration is operated __________.                        switch handle      current is high     'FR'                  winch operator          EL-0102

                 Which plant parameters shown in the illustration would SME #7 CYL.             L.O. PRESS TO     L.O. PRESS. TO          PME #3 MN. BRG.
                 produce an alarm if they fell below preset values?     EXH. and L.O.           MN. ENG. and      MN. ENG and             and SME #7 CYL.
12   866   C                                                                                                                                                      EL-0094
                                                                        PRESS. TO               PME #3 MN. BRG. L.O. PRESS. TO            EXH.
                                                                        RDCN. GR.                                 RDCN. GR.
                 When troubleshooting a console circuit card which is   pull the card and       check for the     de-energize and         check for
                 suspected of being faulty, the first step would be to  measure the value       correct value and pull the card to        continuity of circuit
                 __________.                                            of all resistors        polarity of all   visually inspect for    board traces and
12   867   C                                                                                    power connections burned                  then the gain of
                                                                                                to the card       components              each transistor

                 If the motor fails to start and a voltmeter reading         replace fuse "10A" replace or repair   reset and             check line voltage
                 between 1 and 6, as illustrated, indicates line voltage,                       contact 'Ma'        determine the         between L1 and
12   868   C                                                                                                                                                      EL-0007
                 your next step should be to __________.                                                            cause of the          L2
                                                                                                                    overload
                 What power would be consumed by the series resistor 5 watts                    10 watts            20 watts              40 watts
                 R1 in the circuit shown in the illustration if the source is
12   869   D                                                                                                                                                      EL-0032
                 30 volts, the resistance of R1 is 10 ohms, R2 is 10
                 ohms, and R3 is 10 ohms?
                 The amount of mechanical force or torque produced by strength of its           amount of           length of             all of the above
12   870   D     an electric motor depends on the __________.                 magnetic field    armature current    conductor in the
                                                                                                flow                field
                 Capacitance is the property of an electric circuit          current in the     voltage in the      inductance in the     resistance in the
12   871   B
                 opposing a change in the __________.                        circuit            circuit             circuit               circuit

                                                                               65                                                      Electrical Questions-April 2009
Bk   Num   Ans                           Question                              Answer A               Answer B           Answer C              Answer D          Illustr
                 A megohmmeter is connected to each end of an              an open coil          a loose coil        good continuity      a dirty coil
12   872   C     individual motor winding. A low ohm reading indicates
                 __________.
                 The frequency of an AC generator is controlled by the     rheostat              governor            exciter              capacitor
12   873   B
                 __________.
                 The 'reset' contacts of the master switch shown in the    closed only when      closed only when    opened separately opened when line
                 illustration are __________.                              the master switch     the master switch   by the winch      voltage drops 10%
12   876   A                                                                                                                                                    EL-0102
                                                                           is 'off'              selects a 'run'     operator
                                                                                                 condition
                 The 24 volt DC bus on the emergency switchboard is        general alarm         gyrocompass         smoke detection      all of the above
12   877   D     used to supply power to the __________.                   system                power failure       system
                                                                                                 alarm system
                 The life expectancy of electrical insulation, is          10°C                  25°C                50°C                 100°C
12   878   A     approximately halved for an increased operating
                 temperature of __________.
                 Under normal conditions, storage batteries used for       Trickle charging      Fast charging       Equalizing charge Reverse charging
                 starting the emergency diesel generator are
12   879   A
                 maintained in a charged state by which of the
                 following methods?
                 As shown in the illustration, which set of conditions,    50°F and 3.3 volts 180°F and 6.0          750°F and 0-10       900°F and 7.5
                 evident to the operator and the 'set point module'                           volts                  volts                volts
12   880   D     respectively, will result in a high exhaust temperature                                                                                        EL-0094
                 alarm on the 'starboard main engine'?

                 At high discharge rates, nickel-cadmium storage           require fewer cells   are able to         can be charged       have no individual
                 batteries are superior to lead-acid batteries because     for the same          produce higher      and discharged       cells to replace at
12   881   C     they __________.                                          voltage and less      voltages and do     many times           the end of useful
                                                                           mounting space        not have to be      without much         life
                                                                                                 charged as often    damage
                 A megohmmeter can be used to test for __________.         an open field coil    a shorted field     undercut mica        reversed polarity
12   882   A
                                                                                                 pole
                 The frequency of an alternator is controlled from the     frequency meter       voltage regulator   governor control     synchroscope
12   883   C     main switchboard by adjusting the __________.                                                                            switch

                 The reversal of an AC, three-phase, induction motor is changing all three reversing the        interchanging any interchanging any
                 accomplished by __________.                            motor leads        position of the slip two of the three  two brushes
12   884   C
                                                                                           rings                motor leads




                                                                             66                                                        Electrical Questions-April 2009
Bk   Num   Ans                             Question                           Answer A                 Answer B              Answer C               Answer D          Illustr
                 When troubleshooting a console circuit card suspected test transistors or        blow any              pull the card, clean   de-energize the
                 of being faulty, first check for proper voltages to the integrated circuits      accumulated dust      the sliding            card and check
                 card and then __________.                               for gain and             from the card with    connections with a     the printed circuit
                                                                         compare with             at least 30 psi air   pencil eraser, and     traces for
12   885   C                                                             manufacturer's           from the ship's       remove                 continuity with an
                                                                         specifications           service air system    accumulated dust       ohmmeter



                 A useful instrument for checking 3 phase A.C. motor          hand or battery-    vibrating-reed        hook-on voltmeter- D'Arsonval iron-
12   886   C     performance by measuring possible unbalanced                 operated megger     frequency meter       ammeter            vane probe
                 currents is the __________.
                 In an AC circuit, the inductive reactance of a coil varies   resistance of the   frequency of the     voltage of the          current of the
12   887   B
                 with the __________.                                         circuit             circuit              circuit                 circuit
                 Complete maintenance of electrical motors should             vibration           watertight integrity speed droop             reactive power
12   888   A     include periodic checks for machine __________.

                 As shown in the illustration, the D.C. motor's direction     polarity of the     direction of three-   direction of       polarity of the
12   889   A     of rotation in changed by changing the __________.           generator field     phase motor           generator rotation motor field               EL-0101
                                                                                                  rotation
                 In order to take a current reading with a 'clamp-on'         should remain       cannot touch the      must be fully          will act as a
12   890   C     ammeter, the instrument's jaws __________.                   open                adjacent              closed                 transformer
                                                                                                  conductor                                    primary
                 The number of cycles per second occurring in AC        phase angle               frequency             wave form              half mode
12   891   B
                 voltage is known as the __________.
                 Which plant parameters shown in the illustration would SME #7 CYL.               L.O. PRESS. TO L.O. PRESS. TO                PME #3 MN. BRG.
                 produce an alarm if they exceeded preset values?       EXH. and L.O.             MN. ENG. and    MN. ENG. and                 and SME #7 CYL.
12   892   D                                                                                                                                                         EL-0094
                                                                        TO RDCN. GR.              PME #3 MN. BRG. L.O. TO RDCN.                EXH.
                                                                                                                  GR.
                 What is the approximate discharge voltage produced           1.25 volts          1.5 volts       2.2 volts                    6.0 volts
12   893   A     by one cell of a wet type nickel-cadmium battery?

                 When checking for a possible single phase condition in Meggar                    amp-probe             growler                All of the above.
                 a three-phase induction motor circuit, which of the
12   894   B     following electrical measuring devices would be the
                 most practical to use to locate the malfunction?

                 What would be the power consumed in the combined 5 watts                         10 watts              20 watts               40 watts
                 parallel section of the circuit shown in the illustration if
12   896   C     the source were 30 volts and the resistance for R1 is                                                                                               EL-0032
                 10 ohms, R2 is 10 ohms, and R3 is 10 ohms?



                                                                                67                                                      Electrical Questions-April 2009
Bk   Num   Ans                         Question                                    Answer A                Answer B         Answer C                Answer D            Illustr
                 Sparking of D.C. motor brushes can be caused by               an open                 many mechanical, an open interpole      all of the above
                 __________.                                                   commutating             electrical or
12   897   D
                                                                               winding                 operating faults

                 In an emergency, the fastest way to interrupt power           mate to open the winch operator to          engine room       electrician to open
                 and stop the winch shown in the illustration is for the       disconnect switch open the 'safe            watch engineer to the test link at the
12   898   B     __________.                                                   at 'L1' and 'L2'  switch' at the            open the winch    controller                EL-0102
                                                                                                 'master switch'           circuit breaker

                 A hydrometer is used to measure the __________.               specific gravity of     water pressure in   amount of potable power developed
                                                                               a battery               a deck pipeline     water a vessel is by a salt water
12   899   A
                                                                               electrolyte                                 taking on         service pump

                 The 'reset' contacts of the master switch shown in the        low voltage             overload            low voltage         high power factor
12   900   C     illustration provides the winch controller with               release                 protection          protection          correction              EL-0102
                 __________.
                 When troubleshooting an alkaline storage battery, a           checking the            visually inspecting load testing each   measuring the
                 weak or dead cell is best located by __________.              specific gravity of     each cell's         cell with a         electrolyte
                                                                               each cell               electrolyte level   voltmeter           temperature with
12   901   C                                                                                                                                   an accurate
                                                                                                                                               mercury
                                                                                                                                               thermometer
                 When a megohmmeter is used to test the dielectric             good insulation         the leakage of      the capacitance of the dielectric
                 strength of wire insulation, the initial dip of the pointer                           current along the   the circuit        absorption effect
12   902   C
                 toward 'zero' is caused by __________.                                                surface of dirty                       of the insulation
                                                                                                       insulation
                 The voltage of an operating AC turbo generator is             exciter generator       synchronizing       phase sequence      generator field
12   903   D     raised or lowered by adjusting the __________.                governor controls       switch              switch              exciter

                 Electrical insulation is classed by the __________.           International           approximate        U.S. Coast Guard temperature
                                                                               Association of          operating voltage                      stability of the
12   905   D
                                                                               Electrical              and current                            manufacturing
                                                                               Manufacturers           expected                               material(s)
                 In D.C. motor construction, commutating windings are          opposite main           interpoles         adjacent main       the rotor core
12   906   B
                 wound on __________.                                          poles                                      poles
                 When troubleshooting motor controllers, a shorted             a resistance            charred insulation a reading of 'zero' a higher-than-
                 relay or contactor coil is often indicated by                 reading of 'infinity'   and/or a blown     on a megger from normal voltage
12   908   B     __________.                                                   on an ohmmeter          control fuse       one of the coil's   reading across the
                                                                                                                          leads to ground     winding

                 When a battery-charging panel is being used, the              DC voltage is           the polarity is     the voltage         too little current is
12   909   B
                 batteries will discharge if __________.                       supplied                reversed            fluctuates          supplied

                                                                                  68                                                      Electrical Questions-April 2009
Bk   Num   Ans                             Question                             Answer A           Answer B          Answer C                  Answer D             Illustr
                 Electric current is the flow of electrons through a       volts/watt           amperes/centimet coulombs/second            ohms/volt
12   911   C     conductor. The rate of this flow is measured as                                er
                 __________.
                 If the pointer on a megger fails to return to 'zero' when megger is out of     megger is          hairsprings are          pointer probably
12   912   B     not being used, the __________.                           calibration          operating normally burned out               stuck in that
                                                                                                                                            position
                 If the driving torque, such as that produced by a diesel the use of            direct coupling       increasing            decreasing
                 engine, creates pulsations when coupled with a           amortisseur                                 governor speed        governor speed
                 synchronous generator operating in parallel, the         windings                                    droop                 droop
12   913   A     generator rotor may be periodically pulled ahead or
                 behind its normal position as it rotates. This hunting
                 condition can be reduced by __________.

                 Which of the following statements represents the          Lay sandpaper        Press the brushes     Increase brush        Apply seating
                 FIRST step in seating new brushes on slip rings?          between the brush    against the slip      pressure and run      compound under
                                                                           and the slip ring    ring with a wood      at no load for 3 to   the brushes and
                                                                           and slide the        block.                4 hours.              run at no load for 2
12   914   A                                                               sandpaper back                                                   hours.
                                                                           and forth under
                                                                           the brush.

                 When replacing fuses, always make sure __________. to stand on a     to use insulated                the fuse clips are to increase the
                                                                    rubber mat and    pliers or                       straight, tight, and fuse rating 10% to
12   915   C                                                        use rubber gloves screwdriver                     in good contact      guard against
                                                                                                                                           'nuisance blowing'

                 Periodic testing of circuit breakers is necessary to      can trip faster as it will continue to     does not exceed       be able to
                 assure that a correctly rated and properly installed unit increases in age      provide the          its interrupting      withstand at least
12   916   B
                 __________.                                                                     original degree of   capacity              125% of applied
                                                                                                 protection                                 voltage
                 Voltage will always lead current in a/an __________.      capacitive circuit inductive circuit       magnetic circuit      resistive circuit
12   917   B
                 The need for insulation cleaning may be determined by visual inspection        high megger           low operating    the time period
12   918   A     __________.                                               for dirt             readings              temperature      since the last
                                                                           accumulation                                                cleaning
                 If power were lost to the winch shown in the illustration continue to run at   continue to run but remain stopped     remain stopped
                 while in 'second point hoist' the winch would stop.       'second point        at 'first point'    until the 'safety  until the 'master
                 When power is restored the winch would __________. hoist' unless a             speed, for safety, switch' is recycled switch' is returned
                                                                           different speed is   until the 'master   either directly or to 'off' closing the
12   919   D                                                               selected by the      Switch' is brought by action of the    'reset' contacts            EL-0102
                                                                           'master Switch'      to 'off' and then   'master switch'    and then moved to
                                                                                                back to the         handle             any 'run' position
                                                                                                desired speed

                                                                              69                                                      Electrical Questions-April 2009
Bk   Num   Ans                           Question                               Answer A               Answer B               Answer C               Answer D         Illustr
                 Motor name plate data includes " degrees Centigrade        actual running         permissible           maximum                maximum
                 temperature rise ". This indicates the __________.         temperature of the     temperature rise of   allowable              allowable
                                                                            winding from no        the windings          temperature rise       temperature rise
12   921   B                                                                load to full load      above the             above normal full      for continuous no
                                                                                                   designed ambient      load operating         load service
                                                                                                   temperature           temperature

                 When using a megohmmeter to test the dielectric            good insulation        the leakage of        the capacitance of the dielectric-
                 strength of wire insulation, a continuous series of slight                        current along the     the windings       absorption effect
12   922   B
                 downscale kicks by the pointer is result of                                       surface of dirty                         of the insulation
                 __________.                                                                       insulation
                 You are attempting to parallel two AC generators and higher than the              lower than the bus    the same as the      the same as the
                 the synchroscope pointer is revolving in the slow          bus frequency          frequency             bus frequency but bus frequency,
                 direction. This indicates that the frequency of the                                                     out of phase with it and the circuit
12   923   B     incoming machine is __________.                                                                                              breaker may be
                                                                                                                                              closed at any
                                                                                                                                              pointer position
                 As shown in the illustration, operating the reversing      generator field        generator             motor armature         all of the above
12   924   D     switch will change the polarity of the __________.                                armature                                                          EL-0101

                 Periodic testing by a shore side support technician        heat sensitive         visual pyrotronics    corrosion              electric vibro-
                 using a special camera which can detect potentially        thermography                                 electrolysis           analysis
12   925   A     dangerous loose or corroded bus bar and controller
                 connections is termed __________.

                 When troubleshooting a console circuit card suspected make sure wired             test each resistor    check the              measure the gain
                 of being faulty, first check operating voltages, clean the connections and        and capacitor on      continuity of all      of each transistor
12   926   A     card and then __________.                                  push-on                the card with an      printed circuit        or integrated
                                                                            connectors are         ohmmeter              traces with an         circuit
                                                                            tight                                        ohmmeter
                 Four lamps are connected in parallel in a single circuit. all go out              become dimmer         burn with their        become brighter
12   927   C     If one of the lamp burns out, the others will                                                           original intensities
                 __________.
                 When the electrolyte level of a lead-acid storage          distilled water only   sulfuric acid only    a weak solution of a strong solution
                 battery has decreased due to normal evaporation, the                                                    sulfuric acid and  of sulfuric acid and
12   929   A
                 level should be reestablished by adding __________.                                                     distilled water    distilled water

                 When troubleshooting a motor controller, all indications coil is open             control fuse is       auxiliary contact in relay armature is
                 are that a relay coil should be energized. If there were                          open                  series with the coil stuck
12   930   A     no magnetic pull, with rated voltage measured across                                                    is defective
                 the coil, the most probable cause would be that the
                 __________.

                                                                               70                                                         Electrical Questions-April 2009
Bk   Num   Ans                            Question                                Answer A               Answer B        Answer C                  Answer D         Illustr
                 Discharge switches are often located on hand-driven          megger hand           megger movement tested equipment          tested equipment
                 meggers. The purpose of these switches is to                 generator             coils           while conducting          after testing
12   932   D
                 discharge capacitive charges stored in the                                                         test
                 __________.
                 In the system shown in the illustration, the station at      The selector          There is an open     The contacts to    The switch at
                 section I is unable to signal any other station, nor is      switch is grounded    between terminal     the left of        component "C" is
                 any other station able to signal the station in section I.   at the problem        "C" of the problem   component "B" are stuck open.
                 The station can, however, ring itself by proper              station diverting     station and the      stuck closed
12   934   B     positioning of its selector switch. What is the most         current from the      multi-conductor      allowing only a                           EL-0093
                 probable cause of this problem?                              other stations'       cable to the other   single station to
                                                                              ringing devices.      stations.            respond to itself.

                 If the total source voltage of the three-wire distribution   110.4 volts           112.2 volts          113.0 volts          114.8 volts
12   935   A     system shown in the illustration is 240 volts, what is                                                                                            EL-0075
                 the voltage across load L4?
                 The purpose of the 'heater resistors' for the winch          limit the current in dispel moisture in    keep the winch       maintain winch
                 circuit shown in the illustration is to __________.          the heater circuit the 'master switch'     brake housing        motor operating
12   936   B                                                                                                                                                       EL-0102
                                                                                                   housing & control     below the dew        temperature
                                                                                                   panel                 point
                 When shipboard electrical distribution circuits are          increase, causing increase, causing        decrease, causing    decrease, causing
                 connected in parallel, additional parallel circuits will     a drop in the line a decrease in the       an increase in the   an increase in the
12   937   D
                 cause the total circuit resistance to __________.            current              line voltage          line voltage         line current

                 Which of the listed classes of electrical insulation is      Class 90 (O)          Class 105 (A)        Class 130 (B)        Class 180 (H)
12   938   D
                 suited for the highest operating temperature?
                 Which of the following procedures represents the best        The battery caps      The battery cap      The battery should The battery should
                 method to prevent the freezing of batteries                  should be             vents should be      be kept in a fully be disconnected
12   939   C     continuously exposed to low temperatures?                    removed.              sealed.              charged condition. from its charging
                                                                                                                                            source.

                 Ambient temperature is the __________.                       amount of             temperature of the   normal electric      actual temperature
                                                                              temperature rise of   compartment          motor operating      developed by an
12   941   B                                                                  an electric motor     where the motor is   temperature, less    operating motor
                                                                              with no load          located              the room
                                                                                                                         temperature
                 A ohmmeter can be used to test for __________.               an open field coilsynchronous              undercut mica        reversed polarity
12   942   A
                                                                                                speed
                 You are attempting to parallel two AC generators and use the governor use the governor                  close the circuit    use the field
                 the synchroscope pointer is revolving slowly in the fast control switch to     control switch to        breaker when the     rheostat to adjust
                 direction. You should __________.                        adjust the            increase the             synchroscope         the speed of the
12   943   C                                                              incoming voltage speed of the                  pointer              incoming machine
                                                                          so it is equal to the machine on the           approaches the 0°
                                                                          bus voltage           line only                position

                                                                                71                                                       Electrical Questions-April 2009
Bk   Num   Ans                         Question                                Answer A           Answer B           Answer C                  Answer D         Illustr
                 When the control handle is in the 'off' position, the    de-energized and    energized and the energized and the         de-energized and
12   944   D     solenoid actuated brake of an electric winch is          the brake is        brake is released brake is set by a         the brake is set by
                 __________.                                              released                              spring                    a spring
                 In D.C. motor construction, the armature coils' ends     soldered to the     imbedded into     crimped together          spliced with the
12   945   A     are __________.                                          commutator bar      core slots        with brush pigtails       field windings
                                                                          risers
                 Electric circuits are protected against overloads and    circuit breaker     amplifier            diode                  capacitor
12   946   A
                 short circuits by means of a/an __________.
                 Which of the substances listed should be applied to    Zinc chromate         Lead hydroxide       Lead peroxide          Petroleum jelly
12   949   D
                 battery terminals to help prevent corrosion?
                 When troubleshooting a console circuit card suspected check the fuses        clean dust and       make sure all          substitute a new or
                 of being faulty, the last step would be to __________. and voltage levels    debris from the      connections are        repaired spare
                                                                        of all power          card and burnish     tight including wire   card and check
12   950   D                                                            supplies in the       the sliding          wrappings and          the operation of
                                                                        console               connections          push-on types          the circuit

                 The armature cores of the D.C. motors are constructed eliminate              minimize brush       reduce eddy            compensate for
12   951   C     with laminations to __________.                       hysteresis             sparking             current losses         armature reaction

                 When a megohmmeter is being used to test insulation fluctuating around dipping towards            kicking slightly       continually rising
                 resistance, current leakage along the surface of the a constant         'zero', then rising       downscale as           as the test voltage
12   952   C     insulation is indicated by the megohmmeter pointer   resistance reading slowly                    voltage is applied     is applied
                 __________.

                 While paralleling two (2) AC generators using            running at the      grounded             of the same            in phase
12   953   D     synchronizing lamps only, both lamps will go dark        same speed                               polarity
                 when the generators are __________.
                 The direction of rotation of a DC propulsion motor can   reversing the field reversing the field wiring the field and wiring the field and
                 be reversed by __________.                               connections         and the armature armature in             armature in series
12   954   A
                                                                                              connections         parallel

                 Motor controllers are seldom troubled by grounds         cabinet heaters     special insulation shock mounts on          contactors and
                 because __________.                                      always keep         is used on wire for controller panels       relays are
12   955   D                                                              internal            vital circuits      greatly reduce          mounted on non-
                                                                          components dry                          vibration               conducting panels

                 Which of the listed groups of electrical insulation     impregnated          unimpregnated        pure glass and         mica and porcelain
12   956   C     materials is best suited for the highest operating      cotton and silk      paper and cotton     quartz                 with bonding
                 temperatures?                                                                                                            agents
                 Capacitors can be used in electric distribution systems generator            inductive loads      resistive loads        all of the above
                 to improve power factor. This is accomplished by
12   957   B
                 seesawing energy between the capacitor and the
                 __________.

                                                                            72                                                       Electrical Questions-April 2009
Bk   Num   Ans                           Question                              Answer A          Answer B                 Answer C                Answer D          Illustr
                 The heaters for the winch circuit shown in the            a separate source the winch main           the master switch      the contactor
12   958   A     illustration are powered from __________.                                   bus                      power circuit          control circuit       EL-0102

                 A lead-acid battery cell sustaining a short circuit       will be indicated by will have unusually   will become            cannot be
                 __________.                                               lime accumulation high cell voltage        excessively heated     completely
12   959   C                                                               on the terminal                            while being            discharged under
                                                                           posts                                      charged                load

                 The propeller shaft speed in a turbo-electric,            turbine speed         number of motor      field strength of      field strength of
12   960   A     synchronous, propulsion drive motor is changed by                               poles                the generator          the motor
                 varying the __________.
                 When the voltage and the current developed in an AC       lagging               leading              unity                  infinity
                 circuit reach their peak values at the same time, the
12   961   C
                 power factor is considered to be __________.

                 Which of the instruments listed is used to check       Magneto             Megohmmeter               Dynamometer            Rheostat
12   962   B
                 insulation resistance?
                 You are paralleling two alternators. The synchronizing alternator voltages circuit breaker can       incoming           synchroscope is
                 lamps grow dim and are totally darkened as the         are 180° apart      be closed                 alternator is      defective or
12   963   B     synchroscope pointer approaches the 0° position. This                                                running too slowly broken
                 indicates that the __________.

                 If you reverse both the field and the armature            the direction of    the brushes will       a magnetic lock        the direction of
                 connections to a DC propulsion motor, __________.         motor rotation will become                 will occur in the      motor rotation will
12   964   D
                                                                           change              overheated             motor                  remain the same

                 The turns ratio of device "B" shown in the illustration is 55 volts             110 volts            220 volts              440 volts
                 two to one (total). If 220 volts were applied to
12   965   B     terminals 'H1' & 'H2', what would be indicated across                                                                                             EL-0082
                 'X1' & 'X4' with 'X2' & 'X3' connected and isolated?

                 A fuse will blow for all the listed reasons EXCEPT        excessive vibration extremely hot          loose fuse clips    low contact
12   966   D     __________.                                                                   surroundings                               resistance within
                                                                                                                                          the fuse
                 In the illustration, the component labeled 'EXC' is       a separate class II   a generator          the controller to   the electronic
                 __________.                                               regulated DC          feeding the FLD      drive the governor driver for the
12   968   B                                                               generator for         winding through      for turbo generator switchboard              EL-0003
                                                                           critical direct       the voltage          speed.              metering circuits
                                                                           current loads         regulator.
                 The direction of propeller shaft rotation in a turbo-     polarity of the       polarity of the      phase sequence         phase sequence
12   970   C     electric AC synchronous propulsion drive motor is         propulsion motor      propulsion           of power to the        of power to the
                 changed by reversing the __________.                                            generator            motor                  generator

                                                                              73                                                          Electrical Questions-April 2009
Bk   Num   Ans                           Question                              Answer A               Answer B               Answer C            Answer D        Illustr
                 When voltage and current developed in an AC circuit       lagging                leading                 maximum            minimum
12   971   C     reach their peak values at the same time, the power
                 factor is __________.
                 The direction of rotation of a DC propulsion motor canbrush holder               polarity of the field   brush staggered    motor interpole
12   974   B
                 be changed by reversing the __________.               position                   poles                   order              connections
                 In general, D.C. propulsion motor brush sparking can  incorrect brush            a concentric            a dark chocolate   all of the above
12   976   A     be caused by __________.                              grade, pressure or         commutator              colored
                                                                       position                                           commutator
                 Automatic voltage regulators provided on switchboards regulate the AC            protect the             govern prime       vary the field
                 function to __________.                               load on the                switchboard from        mover speed to     excitation to the
12   977   D
                                                                       generator                  high voltage            control voltage    generators

                 High pressure compressed air should not be used to        it may embed         the surrounding     the air blast dries      a mask and
                 clean electric motors or controller equipment because     metallic particles area may need         out insulation           respirator would
12   978   A
                 __________.                                               into coil insulation additional cleaning quickly                  be required

                 Which of the following problems is indicated if a lead-   Insufficient           A short circuit      The battery is        An excessive
                 acid battery begins to gas violently when it is first     compartment            exists in one of the undergoing its        charging rate is
12   979   D
                 placed on charge?                                         ventilation is being   battery cells.       normal charging       being applied to
                                                                           provided.                                   rate.                 the battery.
                 Moisture absorbed in the windings or condensed on         is good for long       lowers the           will enhance          reduces the
                 the surface of electrical machinery insulation            term preserving        insulation value     insulation            amount of current
                 __________.                                               since most             and is a common resistance only if it      supplied or drawn
12   980   B                                                               insulation is          cause of fault       is fresh water and    by the machine so
                                                                           organic and            grounds in idle      contains no salt      horsepower is
                                                                           contains some          machines                                   limited
                                                                           amount
                 The voltage developed by an AC generator is               speed of the prime AC excitation to            DC excitation to   DC excitation of
12   981   C     controlled by varying the __________.                     mover              the field                   the field          the voltage
                                                                                                                                             regulator
                 In which of the situations listed will a megohmmeter      While the machine While the machine Immediately prior             When the machine
                 give the most accurate readings?                          is in operation.  is discharging      to restarting the           has been shut
                                                                                             static electricity. machine.                    down and
12   982   D                                                                                                                                 grounded for a
                                                                                                                                             period of 15
                                                                                                                                             minutes.
                 You are attempting to parallel two AC generators, and     higher than the        lower than the bus the same as the      the same as the
                 the synchroscope pointer is revolving in the fast         bus frequency          frequency          bus frequency but bus frequency and
                 direction. This indicates that the frequency of the                                                 out of phase with it the circuit breaker
12   983   A     incoming machine is __________.                                                                                          may be closed at
                                                                                                                                          any pointer
                                                                                                                                          position

                                                                             74                                                          Electrical Questions-April 2009
Bk   Num   Ans                         Question                           Answer A                   Answer B              Answer C          Answer D              Illustr
                 Temporary repairs to an open DC propulsion armature connecting the coil        disconnecting coil    grounding the coil removing the
                 coil can be made by __________.                     ends directly to a         ends, insulating      ends and short     sparking brushes
                                                                     pair of negative           each, and short       circuiting the
12   984   B                                                         brushes                    circuiting the two    commutator bar
                                                                                                commutator bars



                 If the total source voltage of the three-wire distribution 110.4 volts         112.2 volts           113.0 volts           114.8 volts
                 system shown in the illustration is 240 volts, what is
12   985   B     the voltage across load L3? [NOTE: Kirchhoff's voltage                                                                                           EL-0075
                 and current laws apply.]

                 As shown in the illustration, most console schematic      make a grid which,   section-off the       allow a record to     indicate, by
                 diagram sheets have letters and/or numbers placed         together with the    book so that each     be kept of how        punching a small
                 across the top and numbers along the side boarders.       sheet numbers,       console function is   often a particular    hole over a letter
                 The purpose of these markings is to __________.           can direct the       marked with the       component             and number, what
12   986   A                                                               engineer to any      same                  represented on        month and year        EL-0099
                                                                           location in the      letter/number         that page has         that particular
                                                                           prints               combination           been tested           page was redrawn



                 When shore power is being connected to a ship in dry      the ship's          proper phase     exactly 450 volts           exactly 60 Hz must
                 dock, __________.                                         generators are      sequence must be must be supplied            be provided by the
                                                                           paralleled with the established      from the shore              terminal
12   987   B                                                               shore power to
                                                                           provide continuous
                                                                           power

                 If a fuse of correct size and type blows frequently,      try the next higher try the next lower     look for trouble      reduce the applied
12   988   C     __________.                                               amperage rating     amperage rating        within the circuit    voltage 10%

                 If violent gassing occurs when a lead-acid storage        battery must be  charging rate is          charging rate is      specific gravity of
                 battery is first placed on charge, the __________.        given an         too low                   too high              the electrolyte
12   989   C
                                                                           emergency charge                                                 solution is too low

                 The purpose of 'R6' in the winch circuit shown in the     maintain dry         keep the series       act as the            limit the armature
                 illustration is to __________.                            conditions within    field current at a    armature dynamic      current during
                                                                           the winch brake      low value during      braking load to       lowering operation
12   990   C                                                               box                  'fourth and fifth     assist the winch in   with heavy loads      EL-0102
                                                                                                point lowering'       stopping

                 The most practical way to control the voltage output of number of              speed of the          strength of the       power factor of the
12   991   C     an AC generator is to vary the __________.              windings               rotating field        rotating magnetic     load
                                                                                                                      field
                                                                              75                                                         Electrical Questions-April 2009
Bk   Num    Ans                           Question                             Answer A               Answer B              Answer C               Answer D           Illustr
                  Which of the instruments listed could be use to locate    Ammeter               Voltmeter              Megohmmeter           Frequency meter
12   992    C     a grounded field coil in a synchronous motor?

                  You are attempting to parallel two AC generators and      the incoming          the incoming           a hazardous           a hazardous
                  the synchroscope pointer stops at a position other than   machine will          machine will trip      condition will be     condition will be
                  0°. If you close the circuit breaker at this moment       accept all of the     out on low voltage     created by the        created by the
                  __________.                                               load                  release                cross current         incoming machine
12   993    C                                                                                                            between the           being at a higher
                                                                                                                         machines              frequency than the
                                                                                                                                               bus

                  Before servicing the device indicated as "A" in panels    have the              only be connected be short circuited         have one lead
                  #1 and #3 of the illustration, the device labeled 'CT'    disconnected          to multimeter on                             grounded to
                  must __________.                                          leads taped to        the ammeter                                  discharge static
                                                                            prevent short         setting                                      electricity for the
12   994    C                                                               circuiting.                                                        prevention of         EL-0003
                                                                                                                                               damage to
                                                                                                                                               electronic
                                                                                                                                               components
                  The devices labeled "L" in Panel 2 of the illustration    load lights           synchronizing          emergency lighting    synchronizing
                  are __________.                                           indicating that the   lights. When the       for the               lights. When the
                                                                            generator breaker     synchroscope is at     switchboard to        synchroscope is at
                                                                            is closed and the     the 12 o'clock         enable the meters     the 12 o'clock
                                                                            generator is          position the lights    to be read in case    position the lights
12   995    D                                                               supplying power to    are on at their        of power failure      are dark indicating   EL-0003
                                                                            the main bus          brightest indicating                         the generators
                                                                                                  that the generators                          are in phase
                                                                                                  are in phase


                  The device labeled 'REG SW' in the illustration is used shift from the          shift the governor     enable the           supply regulated
                  to __________.                                          automatic voltage       control from           operator to read     control power to
                                                                          regulator to the        manual to              the field voltage on the switchboard
12   996    A                                                             manual voltage          automatic/zero         device 'REG ADJ'                            EL-0003
                                                                          regulator               droop                  or device 'MAN
                                                                                                                         ADJ'
                  What type of electric motor is commonly used to start     synchronous           series                 shunt                 cage
12   998    B
                  small auxiliary diesel engines?
                  Violent gassing developed by a lead-acid battery          plate separators      cell voltages are      specific gravity in   charging rate is
12   999    D
                  during charging indicates that the __________.            are grounded          excessive              insufficient          excessive
                  One important difference between wye-connected and        line voltages equal   phase voltages         line current equal    line voltage equal
                  delta-connected generators is that delta connections      to the vector sum     90° out of sync        to the phase          to the phase
12   1001   D
                  have __________.                                          of the phase                                 current               voltage
                                                                            voltages

                                                                              76                                                          Electrical Questions-April 2009
Bk   Num    Ans                          Question                               Answer A                Answer B            Answer C            Answer D             Illustr
                  You are attempting to parallel two AC generators, and higher than the             lower than the bus the same as the     the same as the
                  the synchroscope pointer is revolving fast in the         bus frequency           frequency          bus frequency and bus frequency but
                  clockwise direction. This indicates that the frequency of                                            the circuit breaker out of phase with it
12   1003   A     the incoming machine is __________.                                                                  may be closed at
                                                                                                                       any pointer
                                                                                                                       position
                  A 'dielectric' is a/an __________.                           electrical insulator current flow         good conductor    semiconductor
12   1004   A
                                                                                                                                           material
                  All of the following items can be used in the             a canvas wiper          insulating varnish   abrasive dressing sandpaper
12   1005   B     maintenance of a D.C. propulsion motor's commutator                                                    stones
                  face EXCEPT __________.
                  In the illustration, if one of the devices labeled 'TURB' device labeled          device labeled       operator must        emergency
                  should fail the __________.                               'EXC' will drive the    'BKR' for that       open all the         generator should
                                                                            alternator              alternator should    devices labeled      automatically start
                                                                                                    automatically open   'BKRS' to reduce     and be placed on
12   1006   B                                                                                       because of the       the load on the      line to supply        EL-0003
                                                                                                    reverse power        remaining turbo-     emergency load
                                                                                                    relay                alternator           centers



                  A reverse-power relay will prevent AC generator              automatically        automatically        tripping the panel tripping the
12   1007   D     motorization by __________.                                  redirecting the      speeding up the      board main switch generator circuit
                                                                               load                 prime mover                             breaker
                  When a battery is continuously exposed to low                remove the battery   securely cover the   keep the battery   disconnect the
12   1009   C     temperatures, the best procedure to keep it from             caps                 battery              fully charged      battery
                  freezing is to __________.
                  In the illustration, "D" is the symbol for a/an              thermal overload     portable cable       fuse                 indicating lamp
12   1010   C                                                                                                                                                       EL-0005
                  __________.                                                  heater
                  A galvanometer is an instrument used to measure              thickness of         resistance of        very small         quantity of galvans
                  __________.                                                  galvanized metal     electrical wiring    amounts of current in an electric
12   1012   C
                                                                                                    insulation           or voltage         circuit

                  Complete AC motor controller maintenance includes            periodic testing of checking for loose maintaining a     all of the above
                  __________.                                                  protective devices or worn contacts sufficient supply of
12   1014   D
                                                                                                   and weak springs spare parts

                  If a unloaded DC compound motor's shunt field were           overspeed due to     stop because of      continue to run at   slow down and
12   1015   A     weakened by rheostat resistance or by an open circuit,       reduced CEMF         low flux             base speed           overheat
                  the motor would __________.
                  The purpose of the reverse power relay, provided on a        main circuit         high power           generator            alternator
12   1017   D     ship's service alternator panel, is to trip the circuit in   overload             transfer             overspeeding         motorization
                  the event of __________.

                                                                                 77                                                       Electrical Questions-April 2009
Bk   Num    Ans                           Question                                 Answer A              Answer B             Answer C              Answer D      Illustr
                  When the series field relay "FR" of the winch circuit        shunt Field Relay    "FR" contacts        "FR" contacts         shunt Field Relay
                  shown in the illustration is energized during dynamic        "FR-B.O." is de-     close                open weakening        "FR-B.O." opposes
                  braking the __________.                                      energized and        strengthening the    the shunt field       the series coil's
                                                                               contacts "FR"        shunt field which    which assists in      flux and sets the
12   1018   B                                                                  open setting the     assists in slowing   stopping the motor    mechanical brake  EL-0102
                                                                               mechanical brake     down the motor



                  Which of the following conditions indicates that a lead- Sparks occurring         Unusually high       Low plate             Excessively high
                  acid battery is being charged too rapidly?               at the positive          electrolyte specific potentials being      temperatures and
12   1019   D
                                                                           terminal.                gravity.             developed.            gassing rates.

                  A device which can be used to check the calibration of 500 volt                   portable low         standard digital      clamp-on
                  a circuit breaker is a __________.                     megohmmeter                voltage high         multimeter            voltmeter
12   1020   B
                                                                                                    current testing unit

                  Propulsion DC motor brush pressures can be                   dividing the brush   subtracting the      dividing the spring subtracting the
                  calculated by __________.                                    contact area by      brush contact area   force by the brush spring pressure
12   1021   C
                                                                               the spring           from the spring      contact area        from the brush
                                                                               pressure             pressure                                 contact area
                  How is a wattmeter electrically connected in a circuit?      In series            In parallel          In series-parallel Inductively
12   1022   C
                  The dielectric strength of a vacuum or dry air is            450 volts/inch       1000 volts/inch      20-kv/inch            50-kv/inch
12   1026   C
                  approximately __________.
                  The operating torque of the upper induction disc-type        the main bus         a separate battery line voltage            electromagnets
12   1027   D     element, or timer element, of an AC reverse power                                 source
                  relay is obtained from __________.
                  If the total source voltage of the three-wire distribution   110.4 volts          112.2 volts          113.0 volts           114.8 volts
                  system shown in the illustration is 240 volts, what is
12   1028   C     the voltage across load L2? [NOTE: Kirchhoff's                                                                                                   EL-0075
                  voltage and current laws apply.]

                  As shown in the illustration, the dry-cell batteries are     compound             series               parallel              tandem
12   1029   B                                                                                                                                                      EL-0071
                  connected in __________.
                  In the illustration the symbol for an N/O contact            A                    B                    C                     D
12   1030   B                                                                                                                                                      EL-0005
                  is_______.




                                                                                   78                                                       Electrical Questions-April 2009
Bk   Num    Ans                          Question                                     Answer A             Answer B              Answer C               Answer D         Illustr
                  Which of the following statements represents the               The meter pointer    The meter pointer     The meter pointer      The meter pointer
                  action of a megohmmeter when testing a small                   should               should first swing    should                 should
                  capacitor in good condition?                                   immediately swing    quickly to zero and   immediately swing      immediately swing
                                                                                 to the maximum       then gradually        to infinity and then   to a high reading
12   1031   B                                                                    resistance value     move up the scale     drop in sharp jerks    and gradually
                                                                                 for the capacitor.   as the capacitor      as the voltage         decrease.
                                                                                                      charges.              increases.



                  A wattmeter is used to determine __________.                   the power being      partial circuit       current flowing in a voltage existing
                                                                                 consumed by          resistance            circuit              between two
12   1032   A
                                                                                 electrical                                                      points in a circuit
                                                                                 equipment
                  In the illustrated circuit, if the battery is 24 VDC, the      2 amps               1 amp                 1/2 amp                2.4 amps
                  resistance of R1 is 24 ohms, and the resistance of R2
12   1033   A                                                                                                                                                           EL-0019
                  is 24 ohms, the total current is __________.

                  Which of the following statements is true concerning a Voltage and          Voltage and          Voltage decreases Voltage increases
                  step-down transformer in an operating AC power         current will both be current will both be as current        as current
12   1037   C
                  circuit?                                               increased.           decreased            increases.        decreases.

                  The motor starts when the start button in the illustration     the incorrect        a faulty "M" coil     a dirty contact on a faulty holding
12   1038   D     is pushed, but stops when the button is released the           thermal overload                           the Disc.Sw. at 'L3' relay contact 'Ma'     EL-0007
                  trouble is __________.                                         coil
                  The dry-cell batteries, shown in the illustration are          compound             series                parallel               tandem
12   1039   C                                                                                                                                                           EL-0070
                  connected in __________.
                  When a megohmmeter is used to test the insulation of           good insulation      the capacitance of the leakage of the        the dielectric-
                  a large motor, the initial dip of the pointer toward 'zero'                         the windings       current along the         absorption effect
12   1041   B
                  is caused by __________.                                                                               surface of dirty          of the insulation
                                                                                                                         insulation
                  The illustrated motor fails to start and gives a loud hum disassemble the           push the stop      reset the thermal         hold the "M"
                  when the start button is depressed, your first action     motor to fix the          button to          overload                  contactor closed
                  should be to __________.                                  centrifugal switch        deenergize the "M"                           by hand while
12   1042   B                                                               so the start              coil                                         wearing electrical   EL-0007
                                                                            windings will be                                                       safety gloves to
                                                                            energized                                                              get motor started

                  In the illustrated circuit, what is the total current if the   .8 amps              1.5 amps              .55 amps               2 amps
12   1043   D     voltage is 12 VDC, the resistance of R1 is 15 ohms,                                                                                                   EL-0019
                  and the resistance of R2 is 10 ohms?


                                                                                   79                                                        Electrical Questions-April 2009
Bk   Num    Ans                            Question                              Answer A             Answer B              Answer C             Answer D        Illustr
                  The purpose of resistor bank 'R1-R5' in the winch        limit armature        divert shunt field   limit armature        regulate the
                  circuit shown in the illustration is to __________.      current in lower      current for speed    current in hoist      strength of the
                                                                           and 'series field'    control in both      and 'series field'    brake solenoid 'B1-
12   1045   C                                                              current in hoist to   directions of        current in lower to   B2' in both         EL-0102
                                                                           obtain required       operation            obtain required       directions of
                                                                           speeds                                     speeds                operation
                  Pin #6 of the ahead valve position sensor as shown in    to (-) 50 volts D.C. in parallel with      to (+) 50 volts D.C. to analog common
12   1046   C     the illustration is connected __________.                                     PCOM                                                              EL-0099

                  Which of the listed transformers uses a single winding   Step-up               Step-down            Autotransformers      Isolation
12   1047   C
                  to produce voltage transformation?                       transformers          transformers                               transformers
                  In the illustration what is the minimum wattage needed   12 watts              48 watts             64 watts              232 watts
12   1050   B     for a 3 ohm resistor with a 12 VDC power source in                                                                                              EL-0041
                  circuit "A"?
                  A capacitor is to be tested with a megohmmeter. If the   immediately swing deflect to zero and swing to a high            swing to zero then
                  meter is connected to a shorted capacitor, the meter     to the maximum    remain at that      reading and                gradually increase
                  pointer should __________.                               resistance value  position            gradually                  with slight pointer
12   1051   B                                                                                                    decrease                   movements down
                                                                                                                                            scale

                  The RPM of an AC generator can be measured with           ammeter              voltmeter            vibrating reed        synchroscope
12   1052   C
                  a/an __________.                                                                                    meter
                  The 'dielectric constant' is a numerical value indicating paper or cloth       glass or mica        plastic or Teflon     dry air or a
                  the effectiveness of a dielectric material in comparison                                                                  vacuum
12   1053   D
                  to that of a standard, which is __________.

                  The air gap in an induction motor should be              rotor contact with    axial misalignment damage to the           electrical damage
12   1054   A     periodically checked with a feeler gage to prevent       the stator            of the rotor       motor bearings          to the bearings
                  possible __________.
                  In the illustrated circuit "A", what power is consumed   12 watts              48 watts             64 watts              232 watts
12   1055   B     by a 3 ohm resistor with a 12 volt source?                                                                                                      EL-0041

                  In the illustrated circuit the voltage is provided by a 12 12 hours            1.75 days            30 hours              2.5 days
                  Volt lead acid battery and the resistor value is 3 ohms.
12   1058   C     If the battery is rated for 120 amp-hours, how long will                                                                                        EL-0018
                  it take before the voltage will drop to 1.75 volts per
                  cell?
                  The circuit illustrated represents a 2 wire DC ground      X                   Y                    both will be equal    both will go out.
                  detecting system. If the positive bus is grounded and                                               brightness.
12   1059   C                                                                                                                                                     EL-0008
                  the test button is pushed, which of the lamps will be
                  brightest?


                                                                              80                                                      Electrical Questions-April 2009
Bk   Num    Ans                            Question                           Answer A                   Answer B            Answer C              Answer D           Illustr
                  The hook-on AC volt-ammeter consists essentially of a potential                    control transformer current               reactance
                  split-core and a rectifier-type instrument connected to transformer                                    transformer           transformer
12   1061   C
                  the secondary winding of a __________.

                  Which type of flux should be used when soldering             Silver flux           Rosin flux            Solid flux          Acid flux
12   1062   B     electrical wire connections for electronic components
                  on printed circuit boards?
                  If the pointer of the synchroscope is rotating in the slow   incoming machine      loaded alternator load on the loaded      incoming machine
                  direction (counterclockwise) as you are preparing to         is turning faster     is turning faster alternator is ready     is beginning to
12   1063   B     parallel two alternators, the __________.                    than the load         than the incoming to split                pick up some of
                                                                               alternator            machine                                   the load

                  The air gap in an induction motor should be checked          rotor contact with    changes in        excessive bearing electrical damage
                  periodically with a feeler gage to detect __________.        the laminations       armature magnetic wear              to the rotor
12   1064   C
                                                                                                     strength

                  In the illustration, the assembly labeled 2 is a             wound rotor and       conduction rotor      squirrel cage rotor squirrel cage rotor
                  __________.                                                  shaft for a single    and shaft for a       and shaft for a     for a single phase
12   1065   C                                                                                                                                                        EL-0001
                                                                               phase induction       polyphase             polyphase motor induction motor
                                                                               motor                 induction motor
                  A shore power circuit breaker should be closed only          when the ship's       in a shipyard         if a quick          when the ship's
                  __________.                                                  generators have                             disconnect          generators have
12   1067   D                                                                  been directly                               coupling is used    been removed
                                                                               paralleled to those                                             from the bus
                                                                               on shore
                  In the illustrated device, the part labeled '1A'             are start and run     is the stator for a   is the armature for are direct current
                  __________.                                                  windings for a        polyphase             a squirrel cage     shunt field
12   1069   B                                                                  single phase          induction motor       rotor motor         windings for a        EL-0001
                                                                               shaded pole                                                     universal motor
                                                                               induction motor
                  The progressive operation of the contactors marked           accumulation          dynamic braking       acceleration        regenerative
12   1070   C     "1A" through "4A" provide the winch shown in the                                                                             braking               EL-0102
                  illustration with __________.
                  When a resistor is used as a shunt and is connected in a measurement of            an increased      an extended meter none of the above
                  parallel with a meter movement coil, it will provide   circuit resistance          accuracy of       range
12   1071   C
                  __________.                                                                        approximately 1.5
                                                                                                     percent
                  An internal resistance is placed in series with the meter AC ammeter               DC ammeter        DC voltmeter      Battery
12   1072   C     movement of which of the following instruments?                                                                        hydrometers




                                                                                  81                                                       Electrical Questions-April 2009
Bk   Num    Ans                         Question                                Answer A             Answer B              Answer C              Answer D          Illustr
                  When paralleling two alternators using three             frequency of the     frequency of the      phase rotation of     terminal voltage of
                  synchronizing lamps, the flickering of all three lamps   incoming             incoming              the incoming          the incoming
12   1073   A     becomes progressively slower and slower. This means      generator is         alternator is less    alternators is        alternator is
                  the __________.                                          approaching that     than that of the      opposite to that of   approaching that
                                                                           of the bus           bus                   the bus               of the bus
                  The following air gap readings were obtained from a      The aft bearing      Shims should be       The forward           The aft bearing
                  horizontally mounted, bilge pump, induction motor,       should be            removed from the      bearing should be     should be lowered.
                  equipped with sleeve bearings:                           realigned or         aft bearing.          lowered.
                                                                           replaced.
                                FWD END            AFT END
12   1074   A     Top            .045               .049
                  Right Side     .045               .047
                  Left Side      .045               .047
                  Bottom         .045               .041

                  Which of the following statements is true?
                  The 'dielectric constant' of dry air or a vacuum is      1                    10                    100                   1000
12   1076   A
                  __________.
                  You can determine if a circuit breaker is tripped by     examining the        checking for the      looking for a         looking for the
12   1077   A     __________.                                              position of the      warm breaker          burned-out link       tripped breaker
                                                                           handle                                                           light
                  Proper maintenance of a D.C. motor's commutator          side-cutting the     coating the copper    baking the            all of the above
                  includes __________.                                     copper segments      surface with light    armature in an
                                                                           and undercutting     machine oil for the   oven at 350°C for
12   1079   A                                                              the mica             first four hours of   8 hours annually
                                                                                                operation



                  If the illustrated test is being performed to determine winding is            winding is not        test is               ground is not in
                  which winding is grounded and the light does not come grounded and you        grounded and you      meaningless           the windings but
                  on then __________.                                     should continue on    should continue on    because you can       probably in the
                                                                          to the next winding   to the next winding   not determine if a    pecker head, you
                                                                          to see if any         until the light       winding is            should check and
12   1081   B                                                             others are            comes on              grounded without      re-tape the line      EL-0027
                                                                          grounded              designating that      a megger.             lead connections
                                                                                                winding as
                                                                                                grounded


                  AC voltmeters are generally calibrated to read the   instantaneous            average voltage       RMS voltage           peak voltage
12   1082   C
                  __________.                                          voltage
                  When paralleling two AC generators, the synchroscope bus                      generator on the      oncoming              bus transfer relay
                  selector switch and frequency meter switch should be                          line                  generator
12   1083   C
                  set up to sense the frequency of the __________.

                                                                               82                                                       Electrical Questions-April 2009
Bk   Num    Ans                             Question                                Answer A             Answer B             Answer C               Answer D          Illustr
                  In the illustrated circuit, what is the resistance of R2 if   24 ohms              16 ohms              48 ohms               the answer can
                  the total current is .75 amps, the voltage is 12 VDC                                                                          not be determined
12   1084   C     and the resistance of R1 is 24 ohms?                                                                                          from the              EL-0019
                                                                                                                                                information given

                  In the illustrated ground detection system with a             lamp A will dim or   all three lamps will lamps B and C will    lamp A will start
                  ground on phase A, if the switch is opened                    go out depending     return to their      dim lamp A will be    flickering if the
                  __________.                                                   on the severity of   normal brightness brighter                 ground is in an AC
12   1085   B                                                                   the ground           indicating that the                        induction motor       EL-0009
                                                                                                     bulbs are not burnt
                                                                                                     out

                  In the illustrated circuit, what is the total resistance if 13 1/3 ohms            20 ohms              60 ohms               the answer can
                  the voltage is 10 VDC, the resistance of R2 is 40 ohms                                                                        not be determined
12   1086   A     and the total current is .75 amps?                                                                                            from the              EL-0019
                                                                                                                                                information given

                  When the operating handle of a molded case circuit       in the 'opened'           in the 'closed'      tripped               reset
12   1087   C     breaker is in the mid-position, it indicates the circuit position                  position
                  breaker is __________.
                  On the meter scale illustrated, while using the R X 100 2,000 ohms                 20 Kohms             200 Kohms             3 Megohms
12   1088   B     scale, the reading at "A" will be __________.                                                                                                       EL-0047

                  Which of the listed conditions occur when selection is        Master switch        Contactors '2M',    Contactors '1M',   Master switch
                  made for 'third point hoist' on the winch shown in the        contacts "5", "6",   '3M', '4M' and '1A' 3M', '1A' and '2A' contacts "3","4",
12   1090   D                                                                                                                                                         EL-0102
                  illustration?                                                 "7", "8", and "9"    pick up.            drop out.          "6", "8", and "9"
                                                                                close.                                                      close.
                  If there is a reduction in the normally supplied              run at a slower      operate at a lower vibrate excessively trip off the line
                  frequency to a 120/240 volt, three-phase AC current           speed                current
12   1091   A
                  motor from 60 hertz to 55 hertz, the motor would
                  __________.
                  Which of the following electric meter movements uses D'Arsonval                    Electrodynamomet Moving iron-vane          Inclined coil iron-
12   1092   A     a stationary permanent magnet and movable coil?                                    er                                         vane

                  On the meter scale illustrated, while using the R X 100 3.6 ohms                   36 ohms              193 ohms              360 ohms
12   1093   D     scale, the reading at "D" will be __________.                                                                                                       EL-0047

                  If a small electric motor has been submerged in               send it ashore for   rinse it with warm   soak it in a bucket   clean it with
                  saltwater for a short period of time, you should              rewinding            freshwater and       of commercial         carbon
12   1094   B     __________.                                                                        bake it dry in an    solvent and bake      tetrachloride and
                                                                                                     oven                 with internal heat    blow it out with
                                                                                                                                                compressed air

                                                                                  83                                                      Electrical Questions-April 2009
Bk   Num    Ans                           Question                            Answer A                   Answer B                Answer C            Answer D            Illustr
                  On the meter scale illustrated, while using the R X 100 13 ohms                    130 ohms               1.3 kohms            13 kohms
12   1095   C     scale, the reading at "C" will be __________.                                                                                                         EL-0047

                  On the meter scale illustrated, while using the R X 100 70 ohms                    35 ohms                700 ohms             7 kohms
12   1096   D     scale, the reading at "B" will be __________.                                                                                                         EL-0047

                  On the meter scale illustrated, while using the R X 100 60 ohms                    40 ohms                30 ohms              3 kohms
12   1098   A     scale, the reading at "F" will be __________.                                                                                                         EL-0047

                  In a three-phase, open-delta connected transformer,           the phase current            the sum of any two the difference of
                                                                                                     three times the
12   1101   A     the line current is equal to __________.                                                   phase currents
                                                                                                     phase current              any two phase
                                                                                                                                currents
                  Most AC voltmeters are calibrated to indicate         peak-to-peak        root-mean-square average voltage    peak voltage only
12   1102   B
                  __________.                                           voltage             voltage
                  When paralleling two alternators the synchronizing    alternator voltages incoming         incoming           synchroscope
                  lamps grow dim and are totally darkened as the        are 180° apart      alternator is    alternator is in   pointer is defective
12   1103   C     synchroscope pointer approaches the 0° position. This                     running too fast phase with the bus or broken
                  indicates the __________.                                                                  voltage

                  D.C. motor brush adjustment includes attention to             angle with the       brush length and       grade of material    all of the above
                  __________.                                                   commutator and       pigtail tightness      and surface dirt
12   1104   D
                                                                                clearance within                            conditions
                                                                                the holder
                  If the total source voltage of the three-wire distribution    110.4 volts          112.2 volts            113.3 volts          114.8 volts
                  system shown in the illustration is 240 volts, what is
12   1105   D     the voltage across load L1? [NOTE: Kirchhoff's voltage                                                                                                EL-0075
                  and current laws apply.]

                  On the meter scale illustrated, while using the R X 1         30 ohms              72 ohms                720 ohms             7.2 Kohms
12   1106   A                                                                                                                                                           EL-0047
                  scale, the reading at "Z" will be __________.
                  What is the resistance value indicated by the                 2.2 ohms             24 ohms                240 ohms             2,400 ohms
                  multimeter scale illustrated, if the range switch is set at
12   1108   B                                                                                                                                                           EL-0047
                  R X 1 and the needle is at the position indicated by the
                  letter "Y"?
                  The transistors in the illustrated circuit are connected      RC coupling           transformer           Impedance            direct coupling
12   1109   C                                                                                                                                                           EL-0050
                  using what type of coupling?                                                        coupling              coupling
                  Which of the listed conditions occur when '4th point          Master switch         Contactors '2, 3, &   Master switch        Contactors '1 &
                  lower' is selected on the winch shown in the                  contacts "3", "4", 4M' and '1A'             contacts "5", "6",   3M' and '1, 2, &
12   1110   B                                                                                                                                                           EL-0102
                  illustration?                                                 "6", "8", "9", & "10" energize.             "7", "8", and "9"    3A' energize.
                                                                                close.                                      close.
                  One of the generator or motor bearings is generally           rapid brush wear current leakage            excessive field      circulation of shaft
                  insulated from the end housing in order to prevent                                  from the shaft        winding heat         currents induced
12   1111   D
                  __________.                                                                                                                    in the machine's
                                                                                                                                                 frame
                                                                                  84                                                        Electrical Questions-April 2009
Bk   Num    Ans                            Question                                    Answer A             Answer B              Answer C              Answer D            Illustr
                  To limit the current flow through a DC voltmeter to as          high series          high parallel         series inductor        external shunt
12   1112   A     low a value as possible, the moving coil circuit is             resistance           resistance
                  provided with a/an __________.
                  What is the resistance value indicated by the                   1.45 ohms            7.2 ohms              37 ohms                70 ohms
                  multimeter scale illustrated, if the range switch is set at
12   1113   D                                                                                                                                                              EL-0047
                  R X 1, and the needle is at the position indicated by
                  the letter "B"?
                  Encrusted dirt accumulated inside a motor should be             fiber scraper        pointed welding       hammer and             paint scraper
12   1114   A
                  removed with a __________.                                                           rod                   chisel
                  What do the arrow-like symbols at coordinate '33J'              Connection to        Connection to the     Plug-in                Screw connection
12   1115   C     shown in the illustration represent?                            ground.              analog common         connection.            on a terminal          EL-0099
                                                                                                       bus.                                         board.
                  What is the resistance value indicated by the               1.3 ohms                 4.8 ohms              13 ohms                121 ohms
                  multimeter scale illustrated, if the range switch is set at
12   1116   C                                                                                                                                                              EL-0047
                  R X 1, and the needle is at the position indicated by
                  the letter "C"?
                  If all three ground-detection lamps continue to burn at No grounds exist             All three phases      The test switch is     The current
                  equal intensity after the test button is depressed and                               are grounded          faulty                 transformers are
12   1117   A
                  released, which of the listed conditions is indicated?                                                                            shorted out

                  What is the resistance value indicated by the                   8 ohms               6.2 ohms              1.57 ohms              150 ohms
                  multimeter scale illustrated, if the range switch is set at
12   1118   A                                                                                                                                                              EL-0047
                  R X 1, and the needle is at the position indicated by
                  the letter "X"?
                  What is the resistance value indicated by the                   6 ohms               7.0 ohms              1.7 ohms               167 ohms
                  multimeter scale illustrated, if the range switch is set at
12   1119   A                                                                                                                                                              EL-0047
                  R X 1, and the needle is at the position indicated by
                  the letter "R"?
                  What is the resistance value indicated by the                   7.8 ohms             8 ohms                3.6 ohms               .36 ohms
                  multimeter scale illustrated, if the range switch is set at
12   1120   C                                                                                                                                                              EL-0047
                  R X 1, and the needle is at the position indicated by
                  the letter "D"?
                  One of the generator bearing shells is generally                rapid brush wear     residual           excessive field           circulation of shaft
12   1121   D     insulated from the end housing in order to prevent                                   magnetism leak off winding heat              currents
                  __________.
                  Electrostatic forces in high voltage circuits cause             parallax readings    highly intuitive      highly accurate        inaccurate
12   1122   D
                  indicating instruments to give __________.                                           readings              readings               readings
                  The direction of rotation of the winch shown in the             direction of current polarity of voltage   direction of current   polarity of voltage
12   1124   C     illustration is changed by reversing the __________.            through the shunt at 'S1' and 'S2'         through the            at 'L1' and 'L2'       EL-0102
                                                                                  field                                      armature
                  If a circuit breaker that utilizes built-in, current limiting   a blown CLF          a missing CLF         a misaligned           all of the above
                  fuses (CLF's) cannot be closed, the problem may be              plunger holding                            limiter housing
12   1125   D
                  traced to __________.                                           the trip bar in the                        assembly
                                                                                  open position
                                                                                    85                                                         Electrical Questions-April 2009
Bk   Num    Ans                           Question                                 Answer A              Answer B              Answer C             Answer D        Illustr
                  What is the resistance value indicated by the               0.6 ohms               6 ohms               9.6 ohms             .38 ohms
                  multimeter scale illustrated, if the range switch is set at
12   1126   A                                                                                                                                                      EL-0047
                  R X 1, and the needle is at the position indicated by
                  the letter "F"?
                  To check the three line fuses of a three-phase system place the starter in         make sure the      place the leads        place the leads
                  consisting of a three-phase motor, you must                 the 'stop' position    motor is operating across the 'hot'       across the bottom
                  __________.                                                                        at full load to    ends of the fuses      ends of the fuses
12   1127   A                                                                                        guard against a
                                                                                                     false reading

                  If reading the AC voltage from a typical wall outlet, the   1,000 V                250 V                R X 10,000           10 ma/amps
12   1128   B     range switch of the device illustrated should be set to                                                                                          EL-0047
                  __________.
                  If reading the AC voltage from the line lead of a 440       1,000 V                250 V                R X 10,000           Unable to safely
12   1129   A     VAC controller the range switch illustrated should be                                                                        read with this      EL-0047
                  set to __________.                                                                                                           meter.
                  What does the arrangement at coordinates '62E'          Position recording Temperature                  Miniature bridge     Twisted wire pair
12   1130   D     shown in the illustration represent?                    drum and stylus    compensating                 rectifier            within a shield     EL-0099
                                                                                             thyristor
                  If the voltage applied to a moving disk frequency meter increase           decrease                     remain the same      oscillate
                  decreases, while the applied frequency remains the
12   1131   C
                  same, the frequency indication will __________.

                  You are calibrating a multimeter using internal         replace the                measure              set the pointer      change scales to
                  batteries to supply power for resistance                batteries in the           resistance by        using a bridge       the R X 100 scale
                  measurements. However, you are unable to adjust the instrument                     dividing the                              and adjust using
12   1132   A     pointer to 'zero' using the adjustment knob. Therefore,                            voltmeter                                 the 'zero ohms'
                  you should __________.                                                             indication by the                         adjusting knob
                                                                                                     ammeter
                                                                                                     indication
                  When paralleling two alternators, the synchronizing         incoming               alternator voltages synchroscope is       alternator power
                  lamps remain lit as the synchroscope pointer                alternator is          are 180 degrees     defective or          factors are in
12   1133   C
                  approaches the 0°. This indicates the __________.           running too fast       apart               broken                phase

                  Which of the following procedures should be used to         A thin layer of air-   Compressed air       Spraying a solvent   Space heaters
                  maintain a large electric motor during periods of           drying varnish         should be blown      periodically to      should be used to
12   1134   D     inactivity?                                                 should be applied      over areas where     remove carbon        prevent
                                                                              on the windings.       dust is deposited.   dust.                condensation of
                                                                                                                                               moisture.



                                                                                 86                                                         Electrical Questions-April 2009
Bk   Num    Ans                         Question                                Answer A               Answer B               Answer C                Answer D          Illustr
                  When attempting to measure AC current with the           10 MA / AMPS           10 MA / AMPS           10 MA / AMPS           unable to
                  device shown and you are unsure of the range, the        with leads in the (-   with leads in the (-   with leads in the (-   accurately
                  range switch should be set to __________.                10 A) and (+10 A)      COMMON) and (+)        COMMON) and            measure AC
12   1136   D                                                              jacks                  jacks                  (+10 A) jacks          current with this      EL-0047
                                                                                                                                                device as
                                                                                                                                                illustrated
                  When replacing a defective transformer in a paralleled   The secondary          The transformer        The iron core of       The iron core must
                  transformer configuration, which of the following        leads must be          connections must       the transformer        be grounded for
                  actions must be carried out to insure proper operation   grounded for 10        be made as before      must be flashed to     10 minutes to
12   1137   B     of the equipment it serves?                              minutes to remove      with regard to the     pre-magnetize it.      remove any
                                                                           static charges.        indicated polarity.                           residual
                                                                                                                                                magnetism.

                  The illustrated motor controller __________.             is a low voltage       has no low voltage     is a low voltage       must be used with
                                                                           release controller     protection and the     protection             a generator or
                                                                           because the motor      motor may be           controller and         transformer bank
                                                                           will stop when         damaged if the         must be reset if       that is 'wye' wound
                                                                           voltage falls below    voltage drops          the voltage falls      with T2 connected
                                                                           a certain value        below a certain        below a certain        to the neutral
12   1138   B                                                              and automatically      level                  level                                         EL-0023
                                                                           start when normal
                                                                           voltage resumes




                  Which of the listed conditions could indicate the need   Low ambient            Low operating          High dielectric        Low megger
12   1139   D
                  for cleaning electrical insulation?                      temperature            temperature            strength               readings
                  The reactive power drawn by a motor from an AC           used to establish      lost in overcoming     strictly converted     transmitted directly
                  generator is the power which is __________.              the magnetic field     friction in the        to heat generated      through the rotor
                                                                           of the motor           bearings               by current flow        shaft to perform
12   1141   A                                                                                                            through the            useful work
                                                                                                                         windings

                  A multimeter may be damaged by taking a                  voltage reading        current reading        resistance reading resistance reading
                  __________.                                              while in the           while in the           while in the       while in the
12   1142   A
                                                                           resistance mode        voltmeter mode         ammeter mode       voltmeter mode

                  When two AC generators are being paralleled, the         'slow' direction,      'fast' direction, just 'fast' direction, just 'slow' direction,
                  breaker should be closed with the synchroscope           just before the 12     after the 12 o'clock before the 12            just after the 12
12   1143   C
                  pointer rotating in the __________.                      o'clock position       position               o'clock position       o'clock position

                  The speed of a synchronous motor is varied by            interchanging any changing the                changing the input increasing the field
12   1144   C     __________.                                              two of the three  voltage of the              frequency          excitation
                                                                           live leads        system
                                                                             87                                                           Electrical Questions-April 2009
Bk   Num    Ans                             Question                               Answer A               Answer B            Answer C              Answer D          Illustr
                  In the illustration, the component labeled "G"             is lined with           is a one piece       must be UL            can only contain
                  __________.                                                cardboard to            container with       approved for          one cell
                                                                             maintain a              compartments for shipboard use
12   1146   B                                                                moisture                each individual cell                                            EL-0031
                                                                             (electrolyte) barrier
                                                                             between cells

                  When working on electrical circuits containing large       Keep all radio          Measure capacitor Ground the               Check capacitor
                  capacitors, in addition to de-energizing the circuit,      equipment away.         insulation        capacitor                circuit polarity.
12   1147   C
                  which of the listed precautions should also be taken?                              resistance.       terminals.

                  The transistors in the illustrated circuit are connected   RC coupling             transformer          impedance             direct coupling
12   1148   D                                                                                                                                                        EL-0051
                  using what type of coupling?                                                       coupling             coupling
                  Which of the following statements is true of the           The low speed is        The HOL relay will   This controller       If the overload
                  illustrated motor controller?                              used for starting       open the LS          must be used with     relay opens for
                                                                             the motor and           contacts in the      a generator or        high speed the
                                                                             when the                event of an          transformer that is   motor can still be
12   1149   D                                                                controller              overload while       'Wye' wound with      run in low speed.    EL-0023
                                                                             automatically           operating in high    the L2 lead
                                                                             shifts to High          speed.               connected to
                                                                             speed.                                       neutral.

                  In order to prevent the winch shown in the illustration    set the dynamic         set the mechanical disconnect the          open the test link
                  from turning while troubleshooting the controller circuit, brake by clamping       brake by the       brake solenoid at       preventing current
12   1150   D     __________.                                                contact 'DB'            jackscrew          'B1' and 'B2'           flow to the          EL-0102
                                                                             closed                  provided                                   armature

                  The most inefficient method of voltage reduction, from     capacitor               inductor             resistor              transistor
                  the standpoint of power loss, even when placed in
12   1151   C
                  series with the load, is the use of a/an __________.

                  When using a multimeter for resistance                     setting the        adjusting the line plugging each end            using a special
                  measurements, it should be calibrated by clipping the      instrument pointer voltage to calibrate of one test lead           purpose
                  loose ends of the leads together and __________.           at 'zero' ohms     the instrument       into the plus and          resistance
12   1152   A                                                                                                        minus terminals            measuring
                                                                                                                                                instrument (a
                                                                                                                                                bridge)
                  If two AC generators have just been placed in parallel, a balance coil             changing field       adjusting the         a rheostat
12   1153   C     the kilowatt load is initially distributed evenly by                               excitation           governor control
                  __________.                                                                                             settings


                                                                                88                                                        Electrical Questions-April 2009
Bk   Num    Ans                            Question                               Answer A             Answer B              Answer C              Answer D         Illustr
                  In the illustrated motor controller circuit, which         The high and low     This controller can   The lights must be    The wattage of the
                  statement is true?                                         speed lights         be converted for      rated at a wattage    high speed light
                                                                             operate at less      use with a three      equal or greater      must be greater
                                                                             than line voltage    phase motor by        that the motor        than the wattage
                                                                             with a resistor in   connecting the L3     output wattage.       of the low speed
12   1154   A                                                                series.              lead to the LS                              light.               EL-0023
                                                                                                  contact attached
                                                                                                  to the overload
                                                                                                  relay.


                  What type of circuit is on card 'A0AA2' at coordinate      Operational          Digital logic         Square wave         Binary counter
12   1155   A                                                                                                                                                      EL-0099
                  '29Q' shown in the illustration?                           amplifier            inverter              pulse generator
                  Federal Regulations (46 CFR) require the circuit in the    be at the vessel's   not have any          not be used on      All the above are
                  illustration to __________.                                ship's service       resulting ground      systems where the correct
                                                                             generator            currents flow         resulting ground
                                                                             distribution         through hazardous     will interfere with
                                                                             switchboard for      locations on a tank   the operation of
12   1156   A                                                                normal power,        vessel where line     electronic                                 EL-0009
                                                                             normal lighting      to line voltage       equipment
                                                                             and emergency        exceeds 3,000
                                                                             lighting systems.    VAC


                  Which of the following types of insulation will begin to   Varnished cloth      Rubber                Silicon               Asbestos
12   1157   B     deteriorate FIRST as a result of the heat generated in
                  the conductor it surrounds?
                  Seating the brushes on a DC motor is first                 a file for cutting   using fine            emery paper for       course lapping
                  accomplished using __________.                             the approximate      sandpaper on a        the initial cut and   compound,
                                                                             curvature followed   deenergized           crocus cloth for      followed by a
                                                                             by sandpaper for     machine between       the finishing cut     medium and then
                                                                             the final fit        the brush and the                           a fine grade
                                                                                                  commutator to
12   1159   B                                                                                     establish the
                                                                                                  proper curve and
                                                                                                  then a seating
                                                                                                  stone while
                                                                                                  running the motor



12   1161   C     In the illustration, the device E is the______.            bimetal strip        moving contact        trip bar              handle               EL-0033



                                                                               89                                                        Electrical Questions-April 2009
Bk   Num    Ans                          Question                             Answer A                   Answer B            Answer C                Answer D          Illustr
                  Which of the following statements regarding the use of It must be                 You should always    The indicating        An external shunt
                  a current measuring instrument is correct?             connected in               start with the       needle is deflected   is generally
                                                                         series with the            lowest range until   from left to right    utilized where
12   1162   A                                                            circuit.                   a suitable reading   regardless of         current is less than
                                                                                                    is obtained.         polarity.             10 amperes.

                  If a voltage of 125 VDC is applied to the illustrated         11.5 amps           12.5 amps            115 amps              125 amps
                  circuit where the resistance of R1 is 12 ohms, and R2
12   1163   A                                                                                                                                                         EL-0019
                  is 115 ohms, the current will be ___________.

                  In the illustration the component C is the __________. fixed contact              moving contact       connection            trip bar
12   1164   A                                                                                                                                                         EL-0033
                                                                                                                         terminal
                  The transistors in the illustrated circuit are connected      RC coupling         transformer          LC coupling           direct coupling
12   1166   A                                                                                                                                                         EL-0048
                  using what type of coupling?                                                      coupling
                  The transistors in the illustrated circuit are connected      RC coupling         transformer          LC coupling           direct coupling
12   1168   B                                                                                                                                                         EL-0049
                  using what type of coupling?                                                      coupling
                  On the meter scale illustrated, while using the R X 1         1.8 ohms            6.0 ohms             9.4 ohms              0.6 ohms
12   1169   D                                                                                                                                                         EL-0047
                  scale, the reading at "F" will be __________.
                  The winch shown in the illustration operates in any of        Master switch     Contactor '3M' coil Contact '2M' in the Series relay 'FR'
                  the positions with the master switch in the 'lower'           contact 'MS3' may could have an       power circuit may may be open.
12   1170   A     direction, but will not 'hoist' in any of the master switch   have defective    open winding.       be badly corroded.                              EL-0102
                  hoist positions. Which of the listed faults could be the      springs.
                  cause?
                  How many possible states does a binary logic circuit          One                 Two                  Three                 Four
12   1171   B
                  have?
                  A multimeter (Simpson) can be used to measure                 resistance          voltage              current               all of the above
12   1172   D
                  __________.
                  The KW load is evenly distributed between two                 a balance coil      the governor         the field excitation a rheostat
12   1173   B     alternators operating in parallel by adjusting                                    settings
                  __________.
                  Which of the following problems will most likely occur if     The motor will      The motor will run A time delay will       The winding will
                  the starting winding of a split-phase induction motor         overspeed.          at a reduced       stop the motor.         burn out.
12   1174   D
                  failed to cutout once the motor was in continuous                                 speed.
                  operation?
                  The signal to the circuit on card 'A0AA2' at coordinate       non-inverting input inverting input at   non-inverting input inverting input at
12   1175   B     '29Q' shown in the illustration is on the __________.         at pin "20"         pin '16'             at pin "14"         pin '46'                 EL-0099

                  On the meter scale illustrated, while using the R X 1         2.0 ohms            20 ohms              200 ohms              none of the above
12   1176   A                                                                                                                                                         EL-0047
                  scale, the reading at "E" will be __________.
                  When insulation failure produces a low resistance             an open             a short circuit      a ground              a surge
12   1177   B     current path between two conductors, the resulting
                  condition is known as __________.
                  Which of the listed pairs of materials make the best          copper and          glass and mica       dry air and a         doped silicon and
12   1178   B
                  insulators?                                                   aluminum                                 vacuum                germanium
                                                                                  90                                                     Electrical Questions-April 2009
Bk   Num    Ans                             Question                                Answer A          Answer B          Answer C            Answer D                   Illustr
                  In the illustrated circuit, what is the phase relationship   0° in-phase        180° out of phase phase angle of the unable to
                  of the amplifier output compared to the input?                                                    input divided by   determine without
12   1179   B                                                                                                       power factor       the value of the               EL-0022
                                                                                                                                       bias voltage

                  In a logic circuit, the NOT gate function __________.        does not alter a   serves to amplify a must be              reverses an input
                                                                               logical input      given signal level accomplished with logic condition
                                                                                                                      a common
12   1181   D                                                                                                         collector transistor
                                                                                                                      arrangement

                  Before using an all-purpose electric measuring               remove one of the remove all the         calibrate using a      select the proper
                  instrument (multimeter) utilizing internal batteries to      batteries         batteries              known external         resistance range
12   1182   D     supply power for resistance measurements, you                                                         resistance             and calibrate the
                  should FIRST __________.                                                                                                     meter for "zero"
                                                                                                                                               ohms
                  When paralleling two AC generators, the frequency of     controlled by      adjusted with the         slightly greater       slightly less than
                  the incoming machine immediately prior to closing its    placing the        voltage regulator         than the bus           the bus frequency
12   1183   C     breaker should be __________.                            governor switch in                           frequency
                                                                           the automatic
                                                                           position
                  A single-phase induction motor fails to start. The rotor starting winding   centrifugal               centrifugal switch     running winding
                  is spun rapidly with the line switch closed. Having                         mechanism
                  started by this method it is noted that the motor
12   1184   D     fluctuates between a very slow speed and half speed.
                  The problem probably lies in the ______

                  Pin #8 of the astern valve position sensor shown in the to analog common        in series with        to (-) 50 volts D.C. to (+) 50 volts D.C.
12   1185   A                                                                                                                                                         EL-0099
                  illustration is connected __________.                                           PCOM
                  In the illustration if BRANCH NO. 1 is a lighting circuit 15 amps               80% of the            20 amps                30 amps
                  for crew's berthing, 46 CFR requires the maximum fuse                           connected load
12   1186   C                                                                                                                                                         EL-0013
                  rating for that branch to be __________.

                  When attempting to measure a current of less than 10 500 MA                    10 MA / AMPS           10 MA / AMPS           10 MA / AMPS
                  amps with the device shown, the range switch should                            with leads in the (-   with leads in the (-   with leads in the (-
12   1188   D                                                                                                                                                         EL-0047
                  be set to __________.                                                          COMMON) and (+)        COMMON) and            10 A) and (+10 A)
                                                                                                 jacks                  (+10 A) jacks          jacks
                  When disassembling electric motors for maintenance           punch mark frame wrap bearings in        tag and store          all of the above
                  or overhaul, __________.                                     and end bells for lint free cloths if    small parts in a
12   1190   D
                                                                               proper assembly they are to be           box
                                                                                                 reused


                                                                                 91                                                        Electrical Questions-April 2009
Bk   Num    Ans                            Question                                 Answer A          Answer B               Answer C               Answer D          Illustr
                  In a logic circuit the NOR and NAND gate functions            must be           are available in       are exact             have output
                  __________.                                                   accomplished with diode form             opposites with the    conditions that are
                                                                                a common base                            same NOR and          exact opposites to
12   1191   D                                                                   transistor                               NAND inputs           the output
                                                                                arrangement                                                    condition for OR
                                                                                                                                               and AND,
                                                                                                                                               respectively
                  Conductor resistance may be INDIRECTLY measured               voltmeter only       ammeter only        voltmeter and an      frequency meter
12   1192   C
                  by using a/an __________.                                                                              ammeter
                  The winch shown in the illustration will not operate in       contactor coil '3M' resistor 'R8-A2'     contacts '1M' in      master switch
                  any speed in the lowering direction and at an abnormal        has many shorted has an open             the power circuit     contacts 'MS6'
12   1193   B                                                                                                                                                        EL-0102
                  speed in 'first point hoist'. The possible cause is that      turns                                    are badly corroded    have weak springs
                  __________.
                  If the centrifugal switch or relay used for cutting out the   motor will           starting winding    motor will            motor torque will
                  starting winding of a split-phase induction motor fails to    overspeed            will burn out       immediately stall     be above normal
12   1194   B
                  open once the motor is in operation, the __________.                                                   under load            at rated speed

                  In the illustration, the component labeled D is a             fixed contact        moving contact      trip bar              bimetallic strip
12   1195   B                                                                                                                                                        EL-0033
                  __________.
                  In the illustration, the large battery and R(L) are in the    forward bias the     reverse bias the    forward bias the      reverse bias the
12   1198   D                                                                                                                                                        EL-0022
                  circuit to __________.                                        emitter-base         emitter-base        emitter/collector     emitter/collector
                  When a voltage of 115 VDC is applied to the illustrated       66.09 amps           116.74 amps         0.026 amps            0.015 amps
12   1199   A     circuit with a resistance of 1.74 ohms the current will                                                                                            EL-0018
                  be __________.
                  What is the total resistance of the electrical circuit        0.01 ohms            0.10 ohms           1.00 ohms             10.00 ohms
12   1200   C     illustrated if the resistance of R1 is 2 ohms, R2 is 4                                                                                             EL-0021
                  ohms, and R3 is 4 ohms with a 6 volt battery?
                  When a voltage of 95 VDC is applied to the circuit            .187 amps            3.34 amps           5.34 amps             112.8m amps
12   1201   C     illustrated with a resistance of 17.8 ohms the current                                                                                             EL-0018
                  will be________.
                  The true power indicated by a wattmeter depends on            power factor of the angle of coil        inertia of the        high resistance
                  the current flow through the load, the magnitude of the       load                displacement         movable coil          from the load
12   1202   A
                  potential across the load, and the __________.

                  When paralleling two AC generators, the frequency of          slightly less than   the same as the     slightly greater      the same as the
                  the machine coming on-line, immediately prior to              the oncoming         bus frequency       than the bus          bus voltage
12   1203   C
                  closing its breaker, should be __________.                    generator                                frequency
                                                                                frequency
                  A three-phase, squirrel cage, induction motor will run        open stator coils    high power factor   dirty or corroded     reversed
12   1204   A     hot due to __________.                                                                                 slip rings            commutating poles



                                                                                  92                                                        Electrical Questions-April 2009
Bk   Num    Ans                              Question                               Answer A             Answer B            Answer C               Answer D        Illustr
                  In the illustration, the function generators will accept     pass through the     pass through the     do nothing            not cause a speed
                  only a signal of a given polarity, if negative is used for   amplifier M to the   amplifier M to the   because engine        change until the
                  ahead and positive for astern, moving the bridge             astern function      ahead function       room control is       output voltage
12   1205   C     reference in the direction indicated will __________.        generator to open    generator to open    selected              exceeds the value   SE-0002
                                                                               the astern steam     the ahead steam                            of the lube oil
                                                                               valve                valve                                      pressure override

                  In the illustration, moving the engine room reference in cause a positive         cause no change      not cause a           not cause the
                  the direction indicated will __________.                 signal to be sent to     unless the ahead     change until the      ahead valve to
                                                                           the ahead function       speed error          feedback signal       open until the
                                                                           generator creating       contact is closed    from the ahead        negative signal
                                                                           a more positive                               turbine pressure      exceeds the low
                                                                           signal at the                                 reaches a preset      lube oil pressure
12   1206   A                                                              ahead motor                                   level                 override signal     SE-0002
                                                                           supply (SCR's)
                                                                           causing the ahead
                                                                           valve to open



                  The ground indicating light on the main electrical           trace the circuit    check circuit        open the circuit     check all circuits
                  switchboard is indicating a ground. The best                 paths while          resistances with a   breakers on the      for continuity
                  procedure for locating the grounded circuit is to            looking for burned   megohmmeter          distribution panel,
                  __________.                                                  spots                connected            one at a time, until
12   1207   C                                                                                       between the          the lights no
                                                                                                    grounded line and    longer indicate a
                                                                                                    the distribution     ground
                                                                                                    panel framework

                  Peripheral components for the operation of the astern resistors                   operated on +28      located on a          all of the above
12   1209   C     valve position amplifier circuit shown in the illustration                        volts D.C.           separate circuit                          EL-0099
                  are __________.                                                                                        card
                  D.C. propulsion motor brush pressure depends on the multimeter                    manometer            spring scale          compound gauge
12   1210   C     brush grade used and in practice is set with a
                  __________.
                  The unit 'hertz' is equivalent to __________.              coulombs per           revolutions per      revolutions per   cycles per second
12   1211   D
                                                                             second                 second               minute
                  The kilowatt load can be adjusted on a paralleled          field rheostat         governor control     automatic voltage hand tachometer
12   1213   B     generator by using the __________.                                                                     regulators

                  A three-phase, squirrel cage, induction motor will run       improper brush       reversed         shorted stator            high power factor
12   1214   C     hot due to a/an __________.                                  position             commutating pole

                  Which of the listed pairs of materials make the best         dry air and a        tin and lead         doped silicon and     paper and oil
12   1215   D
                  insulators?                                                  vacuum                                    germanium
                                                                                 93                                                         Electrical Questions-April 2009
Bk   Num    Ans                              Question                              Answer A             Answer B              Answer C          Answer D            Illustr
                  In the illustration, the tan and white wires are            in the liquid line   energized and         not grounded so   the water inlet for
                  connected to the solenoid valve. The solenoid valve         before the TXV       open whenever         the unit must be  the ice maker
12   1216   D     is_________.                                                                     the unit is plugged   modified before                           EL-0042
                                                                                                   in                    using aboard ship

                  A current carrying conductor making an electrical           low switchboard   reading of 1.0 on        high switchboard    totally darkened
                  contact with a wiring metal conduit is indicated by a       wattmeter reading the power factor         voltmeter reading   switchboard
12   1217   D
                  __________.                                                                   meter                                        ground-detecting
                                                                                                                                             light
                  In the illustration if the compressor fails to start but the no power between the yellow wire is the overload is           the blue wire from
                  condenser fan motor is running the problem is                L1 and L2        open at the freezer open                     the defrost heater
12   1218   C     __________.                                                                   temperature                                  is open               EL-0043
                                                                                                control switch

                  The reading at "P" on the megger scale shown in the         15 meg ohms          1.5 meg ohms          1.5 kilo ohms       150,000 ohms
12   1219   B                                                                                                                                                      EL-0044
                  illustration, is __________.
                  A DC generator which is used to supply direct current       rotor                stator                exciter             armature
12   1221   C     in order to maintain an AC generator field is commonly
                  known as a/an __________.
                  A volt-ohm-millimeter can be used to check for              continuity           grounds               voltage             all of the above
12   1222   D
                  __________.
                  When paralleling two AC generators, the frequency           slightly less than   the same as the       slightly more than all of the above
                  (cycles) of the incoming generator, just prior to closing   the frequency of     frequency of the      the frequency of
12   1223   C     the circuit breaker, should be __________.                  the generator on     generator on the      the generator on
                                                                              the line             line                  the line

                  A split-phase induction squirrel-cage motor will not        a faulty centrifugal broken rotor bars     worn bearings       all of the above
                  come up to speed, even though the rated voltage,            switch
12   1224   D     rated frequency, and rated load are applied. The
                  suspected trouble could be due to __________.

                  The power requirements for operating the circuits           (+) and (-) 50 volts (+) 28 and (+) 50     (+) 28 volts D.C.  (+) 28 volts and (-)
12   1225   A     shown in the illustration are __________.                   D.C.                 volts D.C.            and 115 volts A.C. 50 volts D.C.          EL-0099

                  The reading at "V" on the megger scale shown in the         40 meg ohms          0.40 meg ohms         4.0 kilo ohms       40,000 ohms
12   1226   D                                                                                                                                                      EL-0044
                  illustration, is __________.
                  A ground is indicated by the ground-detecting system        close all circuit    open the individual change over           check each circuit
                  on the main electrical switchboard. The FIRST step in       breakers in the      circuit breakers,   generators            with a
                  locating the actual ground is to __________.                distribution panel   one by one until                          megohmmeter
12   1227   B                                                                 until the ground     the ground
                                                                              detector indicates   detection system
                                                                              normal               indicates normal


                                                                                 94                                                      Electrical Questions-April 2009
Bk   Num    Ans                             Question                              Answer A           Answer B           Answer C         Answer D                 Illustr
                  In the illustrated circuit, the amplifier is connected in    common emitter     common collector Darlington paired, common base
12   1228   D     what basic configuration?                                                                        capacitor coupled                             EL-0045

                  The advantage of using the illustrated circuit               high input         high current gain   the best stability  the input and
                  configuration is __________.                                 resistance                             with an increase in output are 180
12   1229   C                                                                                                                                                    EL-0045
                                                                                                                      temperature         degrees out of
                                                                                                                                          phase
                  In the illustrated electronic governor, the circuit card     increasing the     send a kilowatt     shutting down the conditioning the
                  connected to the potential and current transformers is       signal strength to signal to the       prime mover in the load through the
                  for __________.                                              the governor to    metering circuit    event of reverse    use of a magnetic
12   1230   A                                                                  maintain constant                      power to protect    amplifier current      EL-0046
                                                                               engine speed with                      from motorization transformer
                                                                               increased load

12   1231   D     Fuses are usually rated in __________.                       watts              amps only           volts only           amps and volts
                  When used for taking resistance measurements, a volt-        a hand cranked     internal storage    the current in the a step down
12   1232   B     ohm-milliammeter is normally powered by                      generator          batteries           circuit being tested transformer
                  __________.
                  When paralleled, AC generators must have the same            frequency          number of phases phase rotation           all of the above
12   1233   D
                  __________.
                  Discoloration of the rotor bars in a squirrel-cage motor     moisture           overheating         vibration             all of the above
12   1234   B
                  is typical evidence of __________.
                  When the master switch for the winch shown in the            'DB' & '2T'        'DB' & '4M'         'FR-B.O.' & 'LV'      '1M' & '1A'
                  illustration is in the 'off' position, and the line & safe
12   1236   C                                                                                                                                                    EL-0102
                  switches are closed, which of the listed relays should
                  be energized?
                  Multiple grounds have developed and were initially           examine the main eliminate the         change over           check each circuit
                  indicated by the ground-detecting system as one              bus bars for signs individual circuits generators            with a
                  ground. The FIRST step in locating the grounds is to         of overheating     one by one until                          megohmmeter
                  __________.                                                                     the ground
12   1237   B                                                                                     detecting system
                                                                                                  no longer indicates
                                                                                                  any grounds

                  To protect the rotor of a motor disassembled for             suspended by wire wrapped in several   supported by flat     returned to the
                  maintenance or overhaul, it should be __________.            slings in one      layers of heavy     wood blocks on        frame as soon as
12   1238   B
                                                                               corner of the shop paper or            the workbench         the bearings are
                                                                                                  cardboard                                 removed
                  Which of the following materials is a good insulator?        steel              aluminum            glass                 copper
12   1239   C
                  In order to decrease the resistance of the 50K pot         to the left          to the right        clockwise             counterclockwise
                  located at '21Q/R' shown in the illustration, the wiper of
12   1240   D                                                                                                                                                    EL-0099
                  the actual component must be moved __________.

                                                                                 95                                                      Electrical Questions-April 2009
Bk   Num    Ans                           Question                                Answer A            Answer B               Answer C            Answer D           Illustr
12   1241    D  Electrical power is expressed in __________.                  ohms               volts                  amps                 watts
                A voltmeter located on a control panel has been               grounded to the    connected to a         installed exactly as grounded to the
                operating correctly for six months, suddenly burns out.       negative side      large resistor         the old installation positive side
12   1242    C  After removing it, it is found that neither side of the                          between the
                meter has been grounded. When installing the new                                 positive side and
                meter it should be __________.                                                   the ground
                Which of the following should be the FIRST step in            Trip the generator Turn off all           Decrease the         Decrease the
                removing a generator from parallel operation?                 off the            electrical             governor setting     cycles of the
12   1243    C                                                                switchboard.       equipment.             on the 'off going'   generator staying
                                                                                                                        generator.           on the line.

                  An overload in which of the listed motors will result in    Fuel pump motor      Steering motor       Condensate pump Forced draft
12   1244    B    the illumination of an indicating light at the propulsion                                             motor           blower motor
                  control station alarm panel?
                  In the illustration, the diode between terminals 16 and     insure that the      compensate for       protect the          act as a filter to
                  17 is to __________.                                        voltage across the   the temperature      electronic           prevent hunting
12   1245    C                                                                governor coil (EG-   difference of the    governor from                              EL-0046
                                                                              3P) never exceeds    governor oil         counter EMF
                                                                              .6 VDC               heating up
                  In the illustration, the diode between terminals 16 and     act as a short       insure that the      improve response act as a filter to
                  17 is to __________.                                        circuit for the      voltage across the   time             prevent hunting
12   1246    A                                                                sensing coil when    coil does not                                                   EL-0046
                                                                              CEMF is applied      exceed 9 volts

                  A current-carrying conductor makes accidental contact low switchboard   high switchboard darkened                          darkened
                  with a wiring conduit. This will be indicated by a    wattmeter reading wattmeter reading switchboard                      switchboard
12   1247    C
                  __________.                                                                                 ground detecting               synchronizing
                                                                                                              lamp                           lamps
                  In the illustration, the component VR1 on the "A1A1"  a Zener diode to  a variable resistor a Zener diode that             a tunnel diode with
                  PCB is __________.                                    regulate the +9   diode to control    regulates the                  a breakdown
                                                                        volt power supply the output to       voltage to terminal            voltage of 6.6
                                                                                          terminal 9 that     9 at 6.6 volts DC              Volts DC
12   1248    C                                                                            controls the input                                                       EL-0060
                                                                                          to terminal 10



                  In the illustrated amplifier, the RESET potentiometer   the gain is              the stability is     feedback is          response time is
                  A1R2 sets the stability of the control loop by changing increased                increased by         increased to the     increased
12   1249    B    the reset time constant. As the potentiometer is turned                          slowing the          summing point at     decreasing            EL-0060
                  clockwise __________.                                                            response time        terminal 5           stability

                  In the illustration, the chemical reaction depicted         battery is being     cell is short        cell is discharging battery is attached
12   1250    C    indicates that the __________.                              charged at a high    circuited                                to a trickle charger   EL-0061
                                                                              rate
                                                                                96                                                       Electrical Questions-April 2009
Bk   Num    Ans                           Question                                Answer A               Answer B               Answer C                 Answer D         Illustr
                  An electrical connection between the wiring of an           eddy current           ground                 impedance              flux leakage
12   1251   B     electric motor and its metal frame is known as a/an
                  __________.
                  Prior to closing the breaker when paralleling two AC        slightly less than the same as the            slightly greater       all of the above
                  generators, the recommended practice is to have the         the line frequency line frequency             than the line
12   1253   C
                  frequency of the incoming machine __________.                                                             frequency

                  If a synchronous motor begins to vibrate severely and an overload                  an open in a field     insufficient           all of the above
12   1254   D     pull out of synchronism, the cause may be                                          coil                   excitation voltage
                  __________.
                  If the illustrated device is fully discharged, what will be The battery will be    The electrolyte will   The electrolyte will   The plates will be
                  the result?                                                 short circuited        be maximum             be maximum             maximum lead
                                                                              because the mud        sulfuric acid,         water, minimum         oxide and sponge
12   1255   C                                                                 space will be filled   minimum water          sulfuric acid.         lead, minimum         EL-0061
                                                                              with lead sulfate                                                    lead sulfate.



                  Accidental grounds in a shipboard electrical system         result in immediate damage circuit            appear on the          damage insulation
                  must be repaired as soon as possible as they will           power outages       breakers                  ground detection       and may cause
12   1257   D
                  __________.                                                                                               system                 outages

                  In the illustration, the component VR2 on the A1            a zener diode to       a variable resistor    a sneer diode that     a tunnel diode with
                  AMPLIFIER MODULE is __________.                             regulate the +9        diode to control       regulates the          a breakdown
                                                                              volt power supply      the output to          voltage to terminal    voltage of 6.6
                                                                              from common            terminal 1 that        2 at 9.1 volts DC      Volts DC
12   1258   C                                                                                        controls the input                                                  EL-0060
                                                                                                     to terminal 10



                  The illustrated test is being conducted on the motor        the bulb needs to      safety procedures      the disconnected       a ground or partial
                  shown in the illustration, if the lamp lights dimly then    be changed to one      need to be             wires are touching,    ground is
                  __________.                                                 with a higher          reviewed because       they need to be        indicated, a check
                                                                              wattage rating         the test presents a    separated and the      with a megger
                                                                                                     severe electrical      test conducted         should confirm the
                                                                                                     shock hazard to        again                  lamp test
12   1259   D                                                                                        the person                                                          EL-0027
                                                                                                     conducting the test
                                                                                                     and anyone
                                                                                                     touching the motor
                                                                                                     frame




                                                                                 97                                                            Electrical Questions-April 2009
Bk   Num    Ans                          Question                               Answer A                Answer B          Answer C               Answer D          Illustr
                  Which component is responsible for energizing              Contactor '3M'         A spring not      Resistor 'B2-R1'       Relay 'FR-B.O.'
                  solenoid 'B1-B2' and releasing the brake for the winch                            shown in the
12   1260   A                                                                                                                                                     EL-0102
                  motor shown in the illustration?                                                  schematic diagram

                  The standard measuring unit of wire by its cross-          cubic mils             circular mils      square millimeter     cubic inch
12   1261   B     sectional area, as used in American wire tables is the
                  __________.
                  The electrical device shown in the illustration is a/an    operating coil         indicating lamp    motor armature        potentiometer
12   1262   D                                                                                                                                                     EL-0077
                  __________.
                  The effect of carrying field excitation excessively high   tendency for the       tendency for the   tendency for the  loss of motor
12   1264   C     on a synchronous motor will result in a __________.        motor to fall out of   motor to           motor to overheat speed regulation
                                                                             step                   overspeed
                  What is the value of the capacitor in the astern valve     100 kFarad             0.5 microfarad     0.5 millifarad        50 kFarad
12   1265   B                                                                                                                                                     EL-0099
                  position circuit shown in the illustration?
                  What is the resistance value indicated by the               10 ohms               100 ohms           200 ohms              1,000 ohms
                  multimeter scale illustrated, if the range switch is set at
12   1266   C                                                                                                                                                     EL-0047
                  R X 1, and the needle is at the position indicated by
                  the letter "A"?
                  In addition to short circuits and sustained overloads,      loose fuse clips      low ambient        low contact           all of the above
12   1267   A     fuses are likely to blow due to __________.                                       temperatures       resistance

                  In the illustration, the small battery and Rb are in the   forward bias to the reverse bias to the a 'reference            a buffer between
                  circuit to apply __________.                               emitter-base        emitter-base        charge' on the          the input ground
12   1268   A                                                                                                                                                     EL-0022
                                                                                                                     input capacitor         and the emitter
                                                                                                                                             ground
                  The greatest single cause of electrical failures is        the breakdown of       overcurrent        high inductance       too frequent
12   1270   A
                  __________.                                                insulation                                                      testing
                  A device used in an electrical circuit to change           current                rectifier          condenser             shunt
12   1271   B     alternating current to direct current, is known as a       transformer
                  __________.
                  In the illustration, when the energy saver switch is in    the mullion and frz the mullion heater the mullion, frz         the range of the
                  the 'lo' position __________.                              flange heaters will and refrig light will flange, defrost       freezer
                                                                             not energize        not energize          heaters will not      temperature
                                                                                                                       energize              control is
12   1272   A                                                                                                                                increased causing    EL-0042
                                                                                                                                             the cut-in temp to
                                                                                                                                             become warmer

                  Two AC generators of the same capacity are operating assume the                   maintain the       have poor             have poor power
                  in parallel. One with a zero speed droop setting and    smaller share of          frequency of the   sensitivity           response
                  the other with a 5% speed droop. If its capacity is not the load                  system             characteristics
12   1273   B     exceeded, the unit whose governor has the zero speed
                  droop setting will __________.

                                                                                98                                                        Electrical Questions-April 2009
Bk   Num    Ans                              Question                                   Answer A              Answer B             Answer C           Answer D           Illustr
                  In the illustrated test, if the lamp fails to light on any of   all three windings     the brushes          the ground is not the test should be
                  the three windings then __________.                             are grounded and       should be set back   in the windings    redone at a higher
                                                                                  the motor should       on the commutator    and the            voltage
                                                                                  be sent out for        and the test         connections to the
12   1274   C                                                                     repair                 redone               motor controller                          EL-0027
                                                                                                                              and the controller
                                                                                                                              should be checked



                  Which of the following statements is true about the             The field rheostat if the generator is      this is a direct     the motor will tend
                  illustrated circuit?                                            is used for manual flat compounded          current elevator     to act like a series
                                                                                  voltage control.   then the field           control with the     motor and
                                                                                                     rheostat needs to        lower and raise      overspeed with the
                                                                                                     be adjusted up at        corresponding with   controller in the full
12   1275   A                                                                                        full load to             the direction that   raise position.        EL-0030
                                                                                                     compensate for           the elevator will
                                                                                                     excessive voltage        travel.
                                                                                                     droop.


                  A fuse will "blow" if __________.                               an electric motor is   the flow of current the electrical        unequal resistors
                                                                                  stopped suddenly       to the protection   current exceeds       are connected in
12   1277   C
                                                                                  by opening a           device is reversed the rated value of     parallel
                                                                                  switch                                     the fuse
                  In the illustrated circuit, what is the voltage measured        24 volts               18.9 volts          5.1 volts             150 millivolts
                  across R1 if the battery is 24 volts, the resistance of
12   1278   C                                                                                                                                                           EL-0036
                  R1 is 34 ohms, and the resistance of R2 is 126 ohms?

                  In the illustrated circuit, what is the resistance across       500 ohms               1,200 ohms           10 ohms              The answer can
                  R2 if the battery voltage is 32 VDC, the resistance of                                                                           not be found with
12   1279   A                                                                                                                                                           EL-0036
                  R1 is 1.2 kohms and the current through R2 is 18.82                                                                              the information
                  milliamps?                                                                                                                       given.
                  As the ahead valve opens as shown in the illustration,          becomes more           becomes more         approaches           approaches
12   1280   B                                                                                                                                                           EL-0099
                  pin #5 of the Sensor __________.                                negative               positive             neutral point        ground potential
                  The inductance of a coil is measured in __________.             ohms                   volts                henries              amperes
12   1281   C
                  As shown in the illustration, what is responsible for           "DBa" contact.         Reset contacts.      Upper set of "LVa" Lower set of "LVa"
                  maintaining the "LV" relay energized when the master                                                        contacts.          contacts.
12   1282   C                                                                                                                                                           EL-0102
                  switch handle is moved away from the "off" position?

                  In the illustrated circuit, what is the voltage of the          12 volts               24 volts             1.5 volts            6.25 volts
                  battery if the resistance of R1 is 150 ohms, the total
12   1283   D                                                                                                                                                           EL-0036
                  resistance is 250 ohms and the current though R2 is
                  25 milliamps?

                                                                                    99                                                        Electrical Questions-April 2009
Bk   Num    Ans                           Question                                   Answer A              Answer B               Answer C              Answer D          Illustr
                  You are reconnecting a three-phase induction motor to        connect the motor      connect the phase      connect the phase     check the supply
                  the supply line. To prevent possible damage to the           and then use the       indicator to the       indicator to the      line phase
                  load, due to the wrong direction of rotation, you should     'jog' button to        motor leads, rotate    supply voltage        sequence and
                  __________.                                                  determine the          the motor by hand      then connect the      motor rotation with
12   1284   D                                                                  direction of           and then connect       motor                 appropriate
                                                                               rotation               to the supply                                indicators, then
                                                                                                      voltage                                      connect
                                                                                                                                                   correspondingly
                                                                                                                                                   marked leads
                  In the illustrated circuit, one advantage of the capacitor as the frequency         the amplifier          the arrangement       good frequency
                  coupling over direct coupling is __________.               decreased the            becomes more           allows the            response.
                                                                             capacitive               efficient at lower     coupling of the
12   1285   C                                                                reactance (Xc)           capacitance.           signal while it                             EL-0048
                                                                             increases                                       isolates the
                                                                                                                             biasing of each
                                                                                                                             stage.
                  If the electricity represented by the wave form in "B"        direct current with   direct current, half   direct current with   clipped to a value
                  were applied to the left side of the illustrated circuit, the the top lead          wave rectified with    the top lead          equal to the
                  output on the right side would be __________.                 positive with         a ripple frequency     negative with         square root of 3
12   1286   C                                                                   respect to the        of 60 hz               respect to the        times the input       EL-0064
                                                                                lower lead                                   lower lead            voltage value

                  The correct term for the illustrated circuit is a          single phase half        three phase half       three phase full      a single phase full
12   1287   C     __________.                                                wave high power          wave rectifier         wave rectifier        wave rectifier        EL-0063
                                                                             rectifier
                  As shown in the illustration, if the applied voltage is 12 0.013 volts              0.131 volts            0.063 volts           0.63 volts
                  volts DC, the resistance of R1 is 110 ohms, and R2 is
12   1288   B                                                                                                                                                            EL-0036
                  10 kohms, what is the voltage measured across R1?

                  Which of the following statements is true regarding the This full wave              Lead "X" will          This bridge circuit All the above are
                  illustrated circuit?                                    bridge should               always be positive     output will be AC true.
                                                                          never be used               (+) with respect to    current suitable for
                                                                          aboard ship                 ground.                electronic circuits
                                                                          because the                                        requiring voltage
12   1289   B                                                             ground on lead "A"                                 regulation.                                 El-0069
                                                                          will show on the
                                                                          ship's ground
                                                                          detection system.

                  Current flowing in only one direction is called              alternating current omni-directional          direct current        sinusoidal current
12   1291   C
                  __________.                                                                      current
                  The proper method of connecting an ammeter in a              A                   B                         C                     All of the above
12   1292   D     circuit is demonstrated by which of the diagrams                                                                                                       EL-0041
                  shown in the illustration?
                                                                                 100                                                            Electrical Questions-April 2009
Bk   Num    Ans                           Question                                    Answer A               Answer B          Answer C             Answer D           Illustr
                  An alternator is being paralleled with one on the line.        increase               not change         decrease             be exactly 60 hertz
                  At the INSTANT the circuit breaker is closed, the
12   1293   C
                  frequency of the incoming alternator will normally
                  __________.
                  If a three-phase induction motor is operated under a           continue to run,       speed up due to    run cooler due to    stop
                  light load and it develops an open in one of its supply        but will vibrate and   the reduced        reduced current
12   1294   A
                  lines, the motor will __________.                              have reduced           number of poles    flow
                                                                                 torque
                  The illustrated device is a __________.                        full wave bridge       half wave bridge   solid state voltage direct current (DC)
12   1296   A                                                                                                                                                         EL-0064
                                                                                 rectifier              rectifier          regulator           filter
                  When a fluorescent lamp fails to light, the trouble can        lamp                   starter            ballast             all of the above
12   1297   D
                  be in the __________.
                  As shown in the illustration if the applied voltage is 12      3.6 watts              72 watts           .0011286 watts       .014243 watts
                  VDC, the resistance of R1 is 110 ohms, and R2 is 10
12   1298   D                                                                                                                                                         EL-0036
                  kohms what is the total power consumed by the
                  circuit?
                  When a voltage of 115 VDC is applied to the illustrated        1.045 amps             225 milliamps      2.045 amps           965.52 milliamps
12   1299   A     circuit with a resistance of 110 ohms the current will be                                                                                           EL-0018
                  __________.
                  In the illustration, 24 volts is applied to the circuit        2 watts                3 watts            6 watts              12 watts
                  where the resistance of R1 is 3 ohms, R2 is 4 ohms,
12   1300   D                                                                                                                                                         EL-0020
                  and R3 is 5 ohms. What is the power consumed in
                  R1?
                  Electric current is the flow of electrons through a            volts                  amperes            coulombs             ohms
12   1301   B     conductor; the rate of this flow is measured in
                  __________.
                  In the illustration,12 volts is applied to the circuit where   1.2 volts              2 volts            6 volts              12 volts
12   1302   C     the resistance of R1 is 10 ohms and R2 is 10 ohms.                                                                                                  EL-0036
                  What is the voltage across R2?
                  Why is it a good practice to have the frequency of the         This allows the  This prevents the The reverse power All of the above.
                  incoming alternator adjusted slightly higher than that of      oncoming machine machine from          relay is prevented
12   1303   D     the loaded alternator when paralleling two alternators?        to accept load   floating on the line. from activating.
                                                                                 immediately.

                  For the illustrated wiring of a three phase alternator,        phase current is    line current is 1.73 there is no           line current is
                  which statement is true about the current?                     1.73 times the line times the phase      relationship          equal to phase
12   1304   D                                                                    current             current              between phase         current               EL-0074
                                                                                                                          current and line
                                                                                                                          current
                  As shown in the illustration if the applied voltage is 12      0.6 amp             0.833 amp            1.2 amps              2.4 amps
                  VDC, the resistance of R1 is 10 ohms, and R2 is 10
12   1306   A                                                                                                                                                         EL-0036
                  ohms what is the total current in the circuit?


                                                                                   101                                                       Electrical Questions-April 2009
Bk   Num    Ans                             Question                                Answer A            Answer B             Answer C             Answer D         Illustr
                  In the illustration, 24 volts is applied to the circuit       16 watts            20 watts             24 watts             28 watts
                  where the resistance for R1 is 3 ohms, R2 is 4 ohms,
12   1308   A                                                                                                                                                     EL-0020
                  and R3 is 5 ohms. What is the power consumed in
                  R2?
                  In the illustration, 24 volts is applied to the circuit       12 watts            20 watts             24 watts             48 watts
                  where the resistance for R1 is 3 ohms, R2 is 4 ohms,
12   1309   B                                                                                                                                                     EL-0020
                  and R3 is 5 ohms. What is the power consumed in
                  R3?
12   1310   D     Battery capacities are given in __________.                   volts               volt-amperes         volt-hours           ampere-hours
                  When a low input voltage is imparted to a device which        primary             secondary            step-down            step-up
12   1311   D     then delivers a high output voltage, the device is            transformer         transformer          transformer          transformer
                  known as a __________.
                  In the illustration, A, B, C and D are 12 volt batteries. a   6 volts             12 volts             24 volts             48 volts
12   1312   C     voltmeter across the output of the circuit will indicate                                                                                        EL-0039
                  __________.
                  The purpose of the item labeled "Z" in assembly No. 2,        keep the rotor in   align the rotor to   dynamically          cool the motor
12   1314   D                                                                                                                                                     EL-0001
                  shown in the illustration is to __________.                   balance             the stator           balance the rotor
                  The reading at "C" on the megger scale illustrated, is        200,000 ohms        2,000,000 ohms       20,000,000 ohms      200,000,000 ohms
12   1315   C                                                                                                                                                     EL-0044
                  __________.
                  When attempting to read AC current with the illustrated       secure power and disconnect the          connect the meter    unable to measure
                  device and are unsure of the range, as a precaution,          test for voltage lead to be tested       to measure           AC current with
                  the first step should be to __________.                                        and connect the         resistance and use   the device as
12   1316   D                                                                                    meter in series         Ohm's law to         shown               EL-0047
                                                                                                                         calculate current



                  Which of the following conditions can lead to the failure Excessive               Insufficient         Corrosion            All of the above
12   1317   D
                  of a resistor?                                            vibration               ventilation
                  As shown in the illustration if the applied voltage is 12 0.6 amp                 0.833 amp            1.2 amps             2.4 amps
                  VDC, the resistance of R1 is 10 ohms, and R2 is 10
12   1318   A                                                                                                                                                     EL-0036
                  ohms what is the current flowing through R1?

                  As shown in the illustration if the applied voltage is 12 3.6 watts               72 watts             7.2 watts            36 watts
                  VDC, the resistance of R1 is 10 ohms, and R2 is 10
12   1319   C                                                                                                                                                     EL-0036
                  ohms what is the total power consumed by the circuit?

                  As shown in the illustration if the applied voltage is 12     3.6 watts           72 watts             7.2 watts            36 watts
                  VDC, the resistance of R1 is 10 ohms, and R2 is 10
12   1320   A                                                                                                                                                     EL-0036
                  ohms what is the total power consumed by R1?

                  A circuit with a blown fuse would be described as a/an short circuit              open circuit         bonded circuit       grounded circuit
12   1321   B
                  __________.
                  The reading at "K" on the megger scale shown in the    400 ohms                   4,000 ohms           40,000 ohms          400,000 ohms
12   1322   D                                                                                                                                                     EL-0044
                  illustration, is __________.
                                                                                  102                                                     Electrical Questions-April 2009
Bk   Num    Ans                           Question                                Answer A               Answer B             Answer C            Answer D          Illustr
                  Two paralleled alternators are operating near rated         Restart the tripped   Strip the board of    Start the           Transfer all vital
12   1323   B     load. If one trips out mechanically, which of the listed    machine               all non-vital         emergency           loads to the
                  actions should be taken FIRST?                              immediately.          circuits.             generator.          emergency bus.
                  As shown in the illustration if the applied voltage is 12   .434 milliamps        .005 amp              6.00 amps           2.4 milliamps
                  VDC, the resistance of R1 is 24 kohms, and R2 is
12   1324   A                                                                                                                                                      EL-0036
                  3610 ohms what is the current flowing through R1?

                  In the illustrated motor controller, the motor fails to     the control fuse is the stop switch is      an open in the "M" fuse "10A" is
                  start. A voltmeter reading between 1 and 6 reads line       the wrong           open                    coil, 'Ma'         blown
                  voltage, while the voltmeter reading between 2 and 6        amperage not                                contact/start
12   1325   B     reads 0 VAC. The problem is __________.                     allowing full                               switch or overload                       EL-0007
                                                                              current to pass                             contacts
                                                                              through
                  Routine maintenance of dry-type transformers should         preventing contact    keeping protective    periodic testing of all of the above
                  include __________.                                         with water or         surfaces and          insulation
                                                                              excessive             insulating            resistance with a
                                                                              moisture              bushings free of      megger
12   1326   D                                                                                       dirt and conductive
                                                                                                    debris



                  The circuit illustrated represents a single phase AC        X                     Y                     Both will be equal both will go out.
                  ground detecting system. If a ground occurs on line                                                     brightness.
12   1327   A                                                                                                                                                      EL-0008
                  "B", which of the lamps will burn the brightest?

                  If the illustrated device has a step-up ratio of 10 to 1    0 volts               110 volts             1000 volts          1100 volts
                  what voltage would be measured at the secondary
12   1329   A     shortly after the primary of the device is connected to                                                                                          EL-0055
                  110 volts DC with a current of 12 amps?

                  In the illustrated circuit, the amplifier is connected in   common base           reverse bias,     common emitter          common collector
12   1330   C     what basic configuration?                                                         negative feedback                                              EL-0022

                  The twisting force developed by a motor and applied to      magnetism             electromotive         torque              voltage
12   1331   C
                  a shaft is called __________.                                                     force
                  The reading at "Z" on the megger scale shown in the         30,000 ohms           300,000 ohms          3,000,000 ohms      30,000,000 ohms
12   1332   C                                                                                                                                                      EL-0044
                  illustration is __________.
                  If field excitation is suddenly lost to an alternator       supply excessive      operate at the        lose its load and become
                  operating in parallel, that alternator will __________.     current to the bus    same load, but        tend to overspeed overloaded and
12   1333   C
                                                                                                    with reduced                            slow down
                                                                                                    voltage


                                                                                  103                                                    Electrical Questions-April 2009
Bk   Num    Ans                          Question                                   Answer A             Answer B           Answer C              Answer D            Illustr
                  Which of the conditions listed will indicate the need to      Higher than         Excessive           Sparking at the       High megger
                  clean the insulation on the windings of an electric           normal operating    vibration at normal brushes.              readings.
12   1334   A
                  motor?                                                        temperature.        speed.

                  In the illustrated amplifier, the base of the transistor is   N type              P type               metal oxide          alloy junction
12   1335   A                                                                                                                                                        EL-0022
                  what type of material?                                                                                 insulator            material
                  Which of the listed devices may be used as a digital          variable resistor   diode                strain gauge         thermistor
12   1336   B
                  device?
                  If all of the ground detection lamps burn with equal          no grounds exist    all phases are       all lamps show a     all of the above
12   1337   A     brilliance, whether the test button is depressed or                               grounded             ground
                  released, then __________.
                  A capacitor discolored due to excessive heat should be        calibrated using a replaced and the      cooled with a        resoldered with
                  __________.                                                   capacitance        reason for the        spray can of         care taken to
                                                                                Wheatstone         overheating found     refrigerant          insure that the
12   1338   B                                                                   bridge                                   approved for this    original cold solder
                                                                                                                         purpose              joint is repaired

                  In the illustration, if branch NO. 1 is a lighting circuit    80% of the          15 amps              20 amps              30 amps
                  for crew berthing, Coast Guard Regulations (CFR)              connected load
12   1339   C                                                                                                                                                        EL-0013
                  require the maximum fuse rating for that branch to be
                  __________.
                  Which of the illustrated lamps would be brighter?             I only              II only              Both I and II would Neither would be
                                                                                                                         be equally bright lit
12   1340   A                                                                                                                                                        EL-0008
                   I. X
                   II. Y
12   1341   C     The unit of electrical power is the __________.               ampere              kilovolt             watt                 farad
                  On the meter scale illustrated, while using the R X 100       3,000 ohms          30,000 ohms          300,000 ohms         3,000,000 ohms
12   1342   A                                                                                                                                                        EL-0047
                  scale, the reading at "Z" is___________.
                  If the energy input is significantly reduced to the prime     continue to        lose its load and     begin to motorize    slow down and
                  mover of one shipboard alternator operating in parallel       operate at no load overspeed             and then trip out    operate at reduced
12   1343   C
                  with others, that alternator will __________.                                                                               load

                  Which of the listed procedures is the best way to tell if     Measure the         Feel the motor and   Watch for telltale   Periodic opening
                  a motor has become overloaded?                                current flow and    judge by the         signs of smoke       of the O/L relay
                                                                                compare it with the temperature.         coming from the      coil
12   1344   A                                                                   motor full load                          motor.
                                                                                current flow as
                                                                                shown on the
                                                                                nameplate.
                  In the illustration, A, B, C, and D are 12 volts in the (-) 48 volts              (+) 48 volts         (-) 24 volts         (+) 24 volts
                  circuit. What is the voltage of the lead connected to C
12   1345   D                                                                                                                                                        EL-0039
                  and D with respect to the lead connected to A and B?


                                                                                  104                                                     Electrical Questions-April 2009
Bk   Num    Ans                           Question                               Answer A            Answer B            Answer C             Answer D        Illustr
                  If a small electric motor is immersed in salt water it    I only              II only              both I and II       neither I or II
                  should be __________.
12   1346   C
                   I. washed in fresh water
                   II. dried in an oven
                  In order to change the direction of rotation of a D.C.    I only              II only              either I or II      neither I or II
                  motor _________.

12   1347   A     I. the field leads must be changed
                  II. the input leads must be changed

                  Some large A.C. motors are equipped with heaters.         I only              II only              either I or II      neither I or II
                  These could be __________.

12   1349   C     I. resistance heaters bolted directly to the frame
                  II. low voltage windings embedded in the motor
                  windings
                  Which way does electron current flow in the illustrated I only                II only              both I and II       neither I or II
                  device?
12   1350   A                                                                                                                                                EL-0079
                  I. A to B
                  II. B to A
                  The unit of electrical resistance is the __________.      ampere              volt                 watt                ohm
12   1351   D
                  With the selector switches set for R X 10,000 and the     1500 ohms           150,000 ohms         1,500,000 ohms      1.5 ohms
                  leads placed in the proper receptacles, the needle
12   1352   C                                                                                                                                                EL-0047
                  settles on the '150' mark of the top scale. What is the
                  resistance value between the leads?
                  When an AC or a DC motor fails to start, the FIRST        motor windings for motor controller     fuse or circuit      motor controller
12   1354   C     step in troubleshooting should be to check the            obvious opens      leads for continuity breaker              leads for grounds
                  __________.
                  Air gap readings should be taken periodically on          determine the      determine the         provide for the      increase machine
                  electrical generation equipment to __________.            amount of varnish condition of the       correct proper       efficiency
                                                                            that can be        bearings              tightening of the
                                                                            applied to correct                       field coil bolts and
12   1355   B                                                               insulation                               correct lateral
                                                                            problems                                 adjustment of the
                                                                                                                     field coils




                                                                              105                                                     Electrical Questions-April 2009
Bk   Num    Ans                           Question                               Answer A               Answer B             Answer C              Answer D           Illustr
                  On some electrical generating equipment one outboard      It should be placed   It is used to short   It should be placed   It should be placed
                  bearing pedestal is insulated from the bedplate. This     from one end of       the + and - in a      across the            from the shaft to
                  should be checked with a millivolt meter and a jumper.    the shaft to the      D.C. generator or     insulating block to   the pedestal while
                  With the millivolt meter connected between the shaft      other to eliminate    Phase A and           increase the shaft    one reading is
                  and the bedplate how should the jumper be used?           shaft currents.       Phase C in an         current to a point    taken, then
                                                                                                  alternator to         where it can be       removed to take a
12   1356   D                                                                                     eliminate the         measured with the     second reading.
                                                                                                  effects of CEMF.      millivolt meter.      This eliminates the
                                                                                                                                              insulating effect of
                                                                                                                                              the bearing.



                  A current-carrying conductor making electrical contact high switchboard totally dark                  low switchboard   all of the above
                  with a wiring conduit will be indicated by a           wattmeter reading switchboard                  wattmeter reading
12   1357   B
                  __________.                                                                ground detecting
                                                                                             light
                  Maintenance of alkaline batteries should include       checking the        replacing the              maintaining a         replacement when
                  __________.                                            electrolyte weekly electrolyte every 5         trickle charge        the volts per cell
12   1358   C
                                                                         using a             years                                            drops below 1.8
                                                                         hydrometer                                                           VDC
                  If deck machinery is expected to be idle for an        have electrical     perform a 'high            water wash the        check run at
                  extended period of time you should____________.        safety gloves       pot' test to               motor and             regular intervals to
                                                                         available in case determine the                controller to         insure correct
                                                                         of electrical shock condition of the           remove any salt       operation and to
12   1360   D                                                            before running      insulation                 that may interfere    renew the internal
                                                                                                                        with smooth           coating of
                                                                                                                        operation             lubrication

                  Ambient temperature is defined as the __________.         amount of             amount of             temperature of the    normal operating
                                                                            temperature rise      temperature           compartment           temperature, less
12   1361   C                                                               with no load          developed by an       where the motor is    the room
                                                                                                  operating motor       located               temperature

                  What is the resistance value indicated by the               220 ohms            240 ohms              2,400 ohms            24,000 ohms
                  multimeter scale illustrated, if the range switch is set at
12   1362   C                                                                                                                                                        EL-0047
                  R X 100, and the needle is at the position indicated by
                  the letter "Y"?
                  After closing the circuit breaker to place two similar      power factor        voltage load          kilowatt load         ampere load
12   1363   C     alternators in parallel, the NEXT step is to balance the
                  __________.


                                                                               106                                                       Electrical Questions-April 2009
Bk   Num    Ans                            Question                             Answer A             Answer B             Answer C          Answer D             Illustr
                  The failure of ball bearings used in electric motors can failure to clean the failure to maintain excess lubrication all of the above
                  result from __________.                                  bearing before       proper alignment forcing the bearing
                                                                           repacking                                full of grease and
                                                                                                                    eliminating all
12   1364   D                                                                                                       areas of
                                                                                                                    expansion



                  If air gap readings for an electrical generating machine the bearings          insulation readings the prime mover     the field coil bolts
                  have changed significantly from the last reading, you                          and machine         thrust bearing      for the proper
12   1365   A
                  should check __________.                                                       cleanliness                             torque values

                  A switchboard ammeter indicates a reading slightly         mechanical          a poor ground for   static electricity in capacitors inside
12   1367   A     above 'zero' when the leads are disconnected, this is      misalignment of     the meter case      the air               the meter storing
                  caused by __________.                                      the meter pointer                                             charges
                  Air gap readings should be periodically taken for          cloth (non-         dial indicator      inside micrometer tapered, long
                  electrical generation equipment. The best tool to use to   metallic) tape                                                blade, feeler gage
12   1368   D
                  take these measurements is a __________.                   measure

                  Air gap readings should be taken on electrical             I only              II only             both I and II       neither I or II
                  generation equipment periodically to __________.

12   1369   D     I. check machine efficiency
                  II. determine the need for cleaning

                  A circuit that has one of two wires in contact with the    grounded circuit    short circuit       series circuit      closed circuit
12   1371   A
                  hull of a ship, is called a __________.
                  The reading at "X" while on the R X 100 meter scale        8 ohms              150 ohms            800 ohms            80,000 ohms
12   1372   C                                                                                                                                                   EL-0047
                  illustrated would be __________.
                  Attempting to parallel an AC generator which is out of     The breaker         The KVA will        The synchronizing The power factor
                  phase with the bus will result in which of the following   should trip.        decrease.           lamps will burn   will be unitized.
12   1373   A
                  problems?                                                                                          out.

                  Air gap readings for electrical generating equipment       I only              II only             both I and II       neither I or II
                  should be taken periodically. This is to __________.

12   1376   C     I. determine the condition of the bearings
                  II. prevent damage to the rotor and stator




                                                                               107                                                    Electrical Questions-April 2009
Bk   Num    Ans                         Question                                      Answer A              Answer B             Answer C               Answer D         Illustr
                  Air gap readings should be taken on electrical                 I only                II only               both I and II         neither I or II
                  generation machinery periodically to __________.

12   1377   B     I. determine the need for cleaning
                  II. check the condition of the bearings

                  If it is required that the coils 'R1-R2-R3' in the indicator   Reverse the 60 Hz No action is              Interchange leads Interchange leads
                  of figure "B", turn opposite to those in the transmitter,      supply              needed.                 'R1' and 'R3'.    'R2' and 'R3'.
12   1378   B                                                                                                                                                           EL-0092
                  as shown in the illustration, what action should be            connections to 'S1'
                  taken?                                                         and 'S2'.
                  A three-phase alternator is operating at 450 volts with        181.4 KW            187.0 KW                194.2 KW              201.4 KW
                  the switchboard ammeter indicating 300 amps. The kw
                  meter currently indicates 163.6 KW, with a power
12   1379   B     factor of 0.7. If the power factor increases to 0.8, the
                  KW meter would then read __________.

                  Which of the following statements is true concerning           The resistance on     The voltage to the    The current to the    The voltage to the
                  step-down transformer operation?                               the primary side is   primary side is the   primary side is the   primary side is
                                                                                 lower than the        same as the           same as the           greater than the
12   1381   D                                                                    secondary side.       voltage from the      current from the      voltage from the
                                                                                                       secondary side.       secondary side.       secondary side.

                  What is the resistance value indicated on the                  6.0 ohms              162.5 ohms            600 ohms              16,250 ohms
                  multimeter scale illustrated, if the range switch is set at
12   1382   C                                                                                                                                                           EL-0047
                  R X 100, and the needle is at the position indicated by
                  the letter "R"?
                  To remove an alternator operating in parallel with             adjust the power      set the desired     open the circuit    remove the load
                  another unit from the main electrical bus, you must            factor on both        voltage on the      breaker on the      from the outgoing
12   1383   D
                  FIRST __________.                                              units                 outgoing alternator outgoing alternator alternator

                  "The following air gap readings were obtained from a           The aft bearing       Shims should be The forward        The aft bearing
                  horizontally mounted, bilge pump, induction motor,             should be             removed from the bearing should be should be lowered.
                  equipped with sleeve bearings:                                 replaced.             aft bearing.     lowered.

                                FWD END          AFT END
12   1385   A     Top            .045             .049
                  Right Side     .045              .047
                  Left Side      .045             .047
                  Bottom         .045             .041

                  Which of the following statements is true?"
                  As shown in the illustration, the motor-generator (M-G) motor and the                motor and the         generator and the main field and the
12   1386   C     set's three-phase motor drives the __________.          generator                    exciter               exciter           interpole field          EL-0101

                                                                                   108                                                       Electrical Questions-April 2009
Bk   Num    Ans                           Question                             Answer A           Answer B              Answer C                     Answer D        Illustr
                  A ground on a particular phase of a three-phase low      high switchboard low switchboard       dark or dim                  bright switchboard
                  voltage distribution system would be indicated by a      wattmeter reading wattmeter reading switchboard                     ground detecting
12   1387   C
                  __________.                                                                                     ground detecting             light
                                                                                                                  light
                  If the bearings of an electrical generator are failing   check the          check the bearing replace the                    replace the thrust
                  more frequently than expected and the lubricating oil is connections to the insulating block on bearing with a               bearing of the
12   1388   B     sludging then you should __________.                     output leads       one end of the unit sealed roller type           prime mover


                  Maintenance of alkaline batteries should include            checking the         replacing the       top off with sulfuric making certain
                  __________.                                                 electrolyte weekly   electrolyte every 5 acid as needed        connections are
12   1390   D
                                                                              using a              years                                     tight and clean
                                                                              hydrometer
                  One item listed on the name plate of a cargo pump           normal               an ambient            minimum heat rise maximum degrees
                  motor is 'degrees centigrade rise.' This number is          temperature          temperature of        from no load to full centigrade rise
12   1391   B     based on __________.                                        change from cold     40°C                  load                 from absolute zero
                                                                              to hot

                  The reading at "M" on the megger scale shown in the         7.1 meg ohms         .71 meg ohms          71 meg ohms           200,000,000 ohms
12   1392   A                                                                                                                                                       EL-0044
                  illustration, is __________.
                  As part of a routine maintenance program for deck           inspect electrical   disassemble           remove motor          Check drum
                  machinery, you should __________.                           wiring and           pushbutton            covers and            switch contact
                                                                              pushbutton           switches and drain    ventilate as          pressure every
                                                                              switches for         water each week       weather permits       three months
12   1393   A                                                                 evidence of
                                                                              corrosion or
                                                                              burned insulation

                  Which of the listed conditions will occur if the polarity   The motor would      The direction of      The direction of      The field pole
                  of the field poles and the direction of current to the      not start.           rotation of the       rotation of the       windings would
12   1394   C
                  brushes of a DC motor were both reversed?                                        armature would be     armature would be     become
                                                                                                   reversed.             unchanged.            overheated.
                  A single-phase induction motor will only start if you       starting winding     centrifugal           centrifugal switch    running winding
                  spin the rotor rapidly with the line switch closed. After                        mechanism
12   1395   D     starting, its speed fluctuates between very slow and
                  half-speed. The problem probably lies in the
                  __________.
                  The illustration shows a fluorescent light fixture. The     component "D" is     the power             component "A" is      component "B"
                  ends of the lamp alternately glow and become dark,          loose and due to     system's voltage is   shorted and           contacts are
                  but the tube will not light. The most probable cause is     the ship's           fluctuating in and    therefore unable to   opening and
12   1396   C     that __________.                                            vibrations makes     out of the range      produce the high      closing thus         EL-0081
                                                                              and breaks           necessary for         voltage required to   prohibiting
                                                                              contact              proper operation      start the lamp        sufficient current
                                                                                                                                               flow
                                                                                109                                                     Electrical Questions-April 2009
Bk   Num    Ans                            Question                              Answer A           Answer B                Answer C               Answer D         Illustr
                  When testing for blown fuses in a three-phase supply      apply the megger apply an ammeter          apply the voltage      ensure the circuit
                  circuit to a motor, you should first __________.          across the tops of diagonally across       tester across the      is de-energized,
                                                                            the line fuses     the top of the first    bottoms of the line    and then use a
                                                                                               line fuse and the       fuses                  continuity tester
12   1397   D                                                                                  bottom of the third
                                                                                               line fuse



                  The illustrated circuits are used to measure              resistance          gauss or magnetic battery discharge capacitance
12   1398   A     __________.                                                                   field strength    rate in Amp-hours                                EL-0024

                  When reading AC current with the multimeter shown in 10 MA/ 10 AMP            10 MA/ 10 AMP          10 MA/ 10 AMP          unable to measure
                  the illustration and you are unsure of the range, the with leads in the (-    with leads in the (-   with leads in the (-   AC current with
12   1399   D                                                                                                                                                      EL-0047
                  range switch should be set to __________.             10 A) and (+10 A)       COMMON) and (+)        COMMON) and            this multimeter
                                                                        jacks                   jacks                  (+10 A) jacks
                  If your multimeter gives a reading in ohms when       continuity of the       an infinite            the presence of a      that the conductor
12   1400   A     testing each end of each conductor of a three-        conductor               resistance             partial ground         is not short
                  conductor cable, this indicates __________.                                                                                 circuited
                  What is the rotor speed of a four pole, 60 cycle,     270 RPM                 540 RPM                873 RPM                1746 RPM
12   1401   D     induction motor operating at full load with 3% slip?

                  Equalization of the power factors of two alternators      manually, by       automatically, by manually,                    automatically, by
                  operating in parallel is accomplished __________.         adjusting the      automatic voltage adjusting the                the designed
12   1403   B
                                                                            governor controls  regulators            output of current        action of the
                                                                                                                     transformers             governors
                  A short circuit in the armature of a DC motor will cause run fast            hum when              spark at the             fail to start
12   1404   C
                  the motor to __________.                                                     energized             brushes
                  In the illustration, when the energy saver switch is in  mullion and frz     mullion heater and mullion, frz flange,        range of the
                  the 'LO' position, the __________.                       flange heaters will refrig light will not defrost heaters will     freezer
                                                                           not energize        energize              not energize             temperature
                                                                                                                                              control is
12   1406   A                                                                                                                                 increased causing    EL-0043
                                                                                                                                              the cut-in temp to
                                                                                                                                              become warmer

                  In a three-phase electrical system, three ground          there is a ground the dark lamp            there are grounds this is a normal
                  detecting lamps are provided. One lamp goes dark          on the line with the must be replaced      on the lines with condition
12   1407   A     and the others increase in brightness when the            dark lamp                                  the bright lamps
                  "ground test" button is pushed. You should conclude
                  that __________.



                                                                              110                                                       Electrical Questions-April 2009
Bk   Num    Ans                              Question                               Answer A            Answer B            Answer C              Answer D          Illustr
                  When replacing component "B" of the circuit shown in        it is polarity       there is a danger   component "D"         it must match the
                  the illustration, it is important to know that              sensitive and must   of phosphor         must be closed        circuit voltage and
                  __________.                                                 be inserted as       poisoning should    during the            component "C"
12   1408   D                                                                 indicated on its     "B"'s bulb break    replacement to        wattage               EL-0081
                                                                              base                                     provide the
                                                                                                                       capacitor's initial
                                                                                                                       charge
                  A load is connected to the secondary of the                 1 amp                10 amps             100 amps              1000 amps
                  transformer illustrated and the current through the load
12   1410   C     is 10 amps. If the step-up ratio is 10 to 1 and the input                                                                                        EL-0055
                  voltage is 110 VAC, what will be the current flow
                  through the primary?
                  The turns ratio of transformer "A" shown in the             15 volts             30 volts            480 volts             960 volts
                  illustration is four to one and all taps are evenly
12   1412   A                                                                                                                                                      EL-0082
                  spaced. If 120 volts were applied to terminals 'H1' and
                  'H3', what would appear at 'X1' and 'X2'?
                  Which of the methods listed is used to start a AC           Residual             Residual            Residual              Rotation by a
                  generator turning?                                          magnetism            magnetism           magnetism             mechanical prime
12   1413   D
                                                                              remaining in the     remaining in the    remaining in the      mover.
                                                                              field poles.         field coils.        armature.
                  The turns ratio of transformer "A" shown in the             37.5 volts           55 volts            220 volts             440 volts
                  illustration is four to one and all taps are evenly
12   1414   C     spaced. If 110 volts were applied to terminals 'X1' and                                                                                          EL-0082
                  'X3', what would be indicated across 'H1' and 'H2'?

                  A load with an impedance of 440 ohms is connected           2.5 amps             25 amps             250 amps              current cannot be
                  across the secondary of the transformer illustrated. If                                                                    determined with
12   1415   B     the input voltage is 110 VAC and the step-up ratio is                                                                      information given     EL-0055
                  10 to 1, what will be the primary current?

                  When a megohmmeter is being used on a alternating grounded                       good                shorted               dirty
                  current machine, the meter pointer will dip toward 'zero'
12   1416   B     and then gradually rise to the true resistance value if
                  the motor insulation is __________.

                  Sound powered telephone units "I", "II", and "III" of the 2, 4 and 6     1, 2 and 3                  3, 5 and 8            1, 2 and 6
12   1418   D     circuit shown in the illustration are identified as 'station                                                                                     EL-0093
                  numbers' __________.
                  The diagram shown in the illustration represents a/an magnetic amplifier common base                 common collector common emitter
12   1425   D     __________.                                                              amplifier                   amplifier        amplifier                  EL-0022



                                                                                111                                                     Electrical Questions-April 2009
Bk   Num    Ans                            Question                             Answer A             Answer B          Answer C                Answer D          Illustr
                  In a three-phase electrical system, three ground          there is a slight   the switch must be there are no           the light bulbs are
                  detecting lamps are provided. If all three lamps          ground on all three replaced           grounds present        of improper
12   1427   C
                  REMAIN at half-brilliance when the ground detecting       phases                                                        voltage
                  test switch is operated, __________.
                  A three-phase alternator is developing 300 amps, with     133 kw              155 kw               187 kw               212 kw
                  a 0.8 power factor, at 450 volts. The power indicated
12   1431   C
                  on the kilowatt meter, located on the main switchboard,
                  will be __________.
                  Which of the listed conditions will occur if dirt and     A partial short     A dead short         Misalignment of      Overspeeding of
12   1434   A     grease are allowed to accumulate between the              circuit.            circuit.             the motor shaft.     the motor.
                  commutator segments of a motor?
                  'Corrosion-resistant material' and 'non-corrodible        plastics            silver               copper-nickel        all of the above
12   1435   D     material' will include which of the following
                  __________.
                  According to the dry cell battery circuit shown in the    1.5 volts           2.0 volts            6.0 volts            12.0 volts
12   1438   A     illustration, what voltage would be indicated at the                                                                                          EL-0034
                  positive and negative terminals?
                  Which of the following statements is true concerning      The circuit is     The circuit is        The controller is    Depressing both
                  the motor controller circuit shown in the illustration?   configured for Low configured for Low    configured for use   the forward and
                                                                            Voltage            Voltage Release.      with a single        reverse buttons
12   1439   A                                                               Protection.                              phase induction      simultaneously,       EL-0004
                                                                                                                     motor.               will cause a
                                                                                                                                          control circuit
                                                                                                                                          overload.
                  From the illustration shown, what can be determined       Generator A has a   The percent speed    Percent speed        Percent speed
                  from the speed droop characteristics of generator A       greater speed       droop is equal for   droop for            droop for
12   1440   C     and generator B?                                          droop value than    both machines at     generator A is       generator B is        EL-0025
                                                                            generator B         62 % load            4.7%                 4.7%

                  The power supplied to a motor is six kilowatts at 120     0.05 Ohms           0.50 Ohms            2.40 Ohms            24.00 Ohms
12   1441   C
                  volts. What is the impedance of the motor?
                  Which of the following statements concerning the          The symbol          The switch uses      The switch           The symbol
                  illustration is true?                                     illustrates a       "either/or" logic.   functions with       illustrates an
12   1442   B                                                                                                                                                   EL-0026
                                                                            computer cable                           analog               overload relay.
                                                                            pin plug.                                parameters.
                  Which of the following statements is true concerning      Maximum voltage     The figures          The figures         Field polarity
                  the following illustration?                               is produced in      represent a basic    represent a basic   reverses from
12   1443   C                                                                                                                                                   EL-0028
                                                                            figures A and C     AC generator         DC generator        figures A to B and
                                                                                                                                         C to D
                  The most effective method of locating a loose             visual inspection   jiggling each by     sounding each bar checking with a
12   1444   C     commutator bar in a D.C. motor is by __________.                              hand                 with a light weight calibrated torque
                                                                                                                     hammer              wrench

                                                                              112                                                     Electrical Questions-April 2009
Bk   Num    Ans                         Question                                  Answer A             Answer B              Answer C               Answer D          Illustr
                  In the generator shown in the illustration, which          A                     B                     C                      D
12   1445   A     conductor has the minimum voltage being induced?                                                                                                   EL-0029

                  The rheostat shown in the generator control schematic voltage regulator          frequency             shunt field coils      series field coils
12   1446   C     will control the current to the __________.                                      regulator                                                         EL-0037

                  What would be the total capacitance of the circuit         66.6 microfarads      150 microfarads       166.6 microfarads 300 microfarads
                  illustrated if the value of capacitor A was 100
12   1447   D                                                                                                                                                        EL-0038
                  microfarads and capacitor B was 200 microfarads?

                  A diesel engine is driving a DC generator as indicated     151 HP                167 HP                185 HP                 200 HP
                  on the power panel shown in the illustration. What is
12   1448   C     the output horsepower developed by the engine if the                                                                                               EL-0040
                  generator is operating at 90% efficiency?

                  The switchboard instrumentation panel shown in the         main AC generator main DC                   variable frequency electric arc welder
12   1449   B     illustration would best be suited for a/an ________ .                        generator                 MG set             controller               EL-0040

                  As shown in the illustration, the nominal output voltage   1.5 volts             3.0 volts             4.5 volts              9.0 volts
12   1450   C                                                                                                                                                        EL-0071
                  of the battery circuit would be ______?
                  The distance between a generator and its load is 100       0.5 volts             1.38 volts            1.90 volts             2.77 volts
                  feet. What would be the approximate total voltage drop
12   1451   D     across a two wire supply cable if the current were 5.5
                  amperes and the resistance of the wire were 2.525
                  ohms per 1,000 feet?
                  An open armature connection in a DC propulsion             low-load operation clogged ventilation      sparking at the        a grounded shunt
12   1454   B
                  motor could be caused by __________.                                          ducts                    brushes                field coil
                  To protect the rotor of a motor disassembled for           suspended by wire stowed upright on         supported by two       returned to the
                  maintenance or overhaul, it should be __________.          slings in one      its shaft                "V" notched wood       frame as soon as
12   1455   C
                                                                             corner of the shop                          blocks                 the bearings are
                                                                                                                                                removed
                  Ships requiring rapid maneuvering response with a          Steam turbine         Direct diesel drive Diesel electric          Gas turbine drive
12   1456   C     high degree of main propeller shaft control are most       drive                                     drive
                  often __________ .
                  Main propeller shaft rotation of a DC diesel-electric      reversing the field   reversing the field   reversing the         reversing the
12   1458   B     ship is normally reversed by __________.                   polarity in the AC    polarity in the DC    diesel engine         interpoles
                                                                             generator             motor                 rotation
                  SCR power converters are used on DC diesel-electric        convert high          regulate DC motor     provide high          All of the above
                  drive ships to __________.                                 voltage AC to DC      current               efficiency electrical
12   1460   D
                                                                                                                         power control

                  A four-pole induction motor, operating on three-phase      850 RPM               1,150 RPM             1,750 RPM              3,550 RPM
12   1461   C     60 cycle current will operate at approximately
                  __________.
                                                                                 113                                                         Electrical Questions-April 2009
Bk   Num    Ans                           Question                              Answer A               Answer B              Answer C             Answer D        Illustr
                  One major advantage of a diesel electric propulsion       excellent              low cost and         less maintenance     lower fuel
12   1463   A
                  plant is __________.                                      maneuverability        weight                                    consumption
                  While standing an "at sea watch" onboard a AC diesel- leading                    lagging              zero                 infinity
                  electric drive ship, you notice that the kwatt load is at
                  roughly 75% of capacity with a power factor less than
12   1465   B     1. The reactive power (kvars) in the main power
                  distribution would be __________.

                  Propulsion AC generators creating 4160 VAC use              4:1                  1:4                  35:1                 40:1
                  transformers to provide 119 volts to the automatic
12   1468   C
                  voltage regulator. The turns ratio of this transformer is
                  __________.
                  Two AC generators are operating in parallel and both        increase the         decrease the         increase the         decrease the
                  are equipped with automatic voltage regulators. While       speed of the         speed of the         voltage of the       voltage of the
                  standing watch, one generator is noted as having a          generator with the   generator with the   generator with the   generator with the
                  greater lagging kvar value. In order to equalize the        largest kvar while   largest kvar while   largest kvar while   largest kvar while
12   1470   D     kvars between the generators you should __________.         decreasing the       increasing the       decreasing the       increasing the
                                                                              other generator      other generator      other generator      other generator
                                                                              speed                speed                voltage              voltage

                  A conductor with a cross-sectional area of one circular 0.1 inches               0.01 inches          0.001 inches         0.0001 inches
12   1471   C     mil would have a diameter of __________.

                  An equalizing connection between two compound-              reverse the          automatically      reverse the          parallel the series
                  wound DC generators when paralleled, serves to              polarity of the      equalize the power direction of current fields of the
                  __________.                                                 incoming             factors            in the series field generators
12   1473   D                                                                 generator as the                        of the incoming
                                                                              series field                            generator
                                                                              weakens
                  If a D.C. motor hums, but does not run when                 Incorrect lead       Incorrect brush      A dirty commutator All of the above
12   1474   D     energized, which of the listed conditions could exist?      connections          setting                                 are correct.

                  Thermal strip heaters are provided in DC main               prevent moisture     maintain a          prevent the rotor     provide an
                  propulsion motors to __________.                            buildup in           relatively constant from warping          additional means
                                                                              windings             temperature in the                        of starting
12   1475   A                                                                                      motor enclosure                           resistance



                  An AC diesel-electric propulsion system requires less       Diesel engine        Propulsion motor     AC generator         Propulsion
                  maintenance than a DC diesel-electric system for                                                                           transformers
12   1476   B
                  which one of the following components?


                                                                                114                                                    Electrical Questions-April 2009
Bk   Num    Ans                          Question                               Answer A            Answer B           Answer C               Answer D      Illustr
                  Main shaft rotation on an AC diesel-electric propulsion increasing the       decreasing the      reversing any two     reversing the
12   1477   C     vessel is normally reversed by __________.               generator           generator           phase leads to the    prime mover
                                                                           frequency           frequency           motor                 rotation
                  A common method used to control the speed of the AC varying the input        increasing the      decreasing the        increasing the
                  propulsion motor on a diesel-electric propulsion ship is frequency of the    motor voltage       motor voltage         current to the
12   1478   A
                  by __________.                                           voltage to the                                                motor
                                                                           motor
                  On electric propulsion drive ships, Silicon-Controlled   I only              II only             Both I and II         Neither I or II
                  Rectifiers can be used to control which of the
                  following?
12   1479   C
                  I. DC propulsion motors
                  II. AC propulsion motors
                  A ships main propulsion electric drive power converter power converter       motor control       lubricating oil       All of the above
                  panel circuit breaker may fail to close due to         cooling fan not       throttle handles    pressure to the
12   1480   D     __________.                                            energized             not in "stop"       main propulsion
                                                                                               position            drive system is
                                                                                                                   insufficient
                  The major advantage of a diesel electric propulsion      low cost and        excellent           less maintenance      lower fuel
12   1482   B     plant is __________.                                     weight              propulsion                                consumption
                                                                                               maneuverability
                  An open in the armature of a DC motor is suspected,      conduct a bar to    visually inspect the conduct an           test the
                  but is not found by visual inspection of the             bar test of the     armature windings insulation              commutator for a
12   1484   A
                  commutator. The next step in troubleshooting this        armature                                 resistance test of   ground
                  problem is to __________.                                                                         the armature
                  If a small electric motor is immersed in salt water it   I only              II only              both I and II        neither I or II
                  should be __________.
12   1486   A
                   I. washed in fresh water and thoroughly dried
                   II. initially started with reduced voltage
                  An autotransformer is equipped with a 50% tap, a 65%     The load is         The load is         The load is           The load is
                  tap, and an 80% tap. Which of the following              receiving minimum   receiving minimum   receiving             receiving
                  statements is true concerning a load connected to the    voltage and         voltage and         maximum voltage       maximum voltage
12   1487   B     50% tap?                                                 minimum current.    maximum current.    and minimum           and maximum
                                                                                                                   current.              current.

                  If a small electric motor is immersed in salt water it   I only              II only             both I and II         neither I or II
                  should be __________.
12   1488   C
                  I. washed in fresh water
                  II. thoroughly dried


                                                                             115                                                    Electrical Questions-April 2009
Bk   Num    Ans                          Question                              Answer A            Answer B             Answer C            Answer D          Illustr
                  The use of a high wattage soldering iron when            The flux may not   The foil circuitry   The solder may      The conductivity of
                  soldering or desoldering components on a printed         spread evenly.     bonded to the        not harden          the solder will
12   1489   B     circuit board may cause which of the following faults to                    board may            properly.           decrease.
                  occur?                                                                      separate from the
                                                                                              surface.
                  What would be the capacitive reactance of the circuit 8.8 ohms              17.7 ohms            39.8 ohms           79.6 ohms
                  shown in the illustration if the capacitance of A was
12   1490   A     100 microfarads, the capacitance of B was 200                                                                                              EL-0038
                  microfarads and the frequency of the source was 60
                  cycles?
                  When troubleshooting an amplifier, you measure an           32 volts        30 volts             28 volts            15 volts
                  output of 30 volts. If the gain of the amplifier is 2, what
12   1491   D
                  must the input voltage be for the amplifier to work
                  properly?
                  What would be the capacitive reactance of the circuit 8.8 ohms              17.7 ohms            39.8 ohms           79.7 ohms
                  shown in the illustration if the capacitance of A was 50
12   1492   B     microfarads, the capacitance of B was 100 microfarads                                                                                      EL-0038
                  and the frequency of the source was 60 cycles?

                  What would be the capacitive reactance of the circuit     1.2 ohms          2.3 ohms             4.4 ohms            8.8 ohms
                  shown in the illustration if the capacitance of A was
12   1493   C     200 microfarads, the capacitance of B was 400                                                                                              EL-0038
                  microfarads and the frequency of the source was 60
                  cycles?
                  If an electric motor fails to start, you should FIRST     phase sequence    ampere load          fuse or circuit     line frequency
12   1494   C
                  check the __________.                                                                            breaker
                  What would be the total capacitance of the circuit        75 microfarads    150 microfarads      2500 microfarads    5000 microfarads
                  illustrated if the value of capacitor A was 100
12   1495   B                                                                                                                                                EL-0038
                  microfarads and capacitor B was 50 microfarads?

                  Increasing the power source frequency in a capacitive     decrease the       not have any        increase the       not have any
                  circuit will __________.                                  average current in affect on the       average current in affect on the
12   1496   C
                                                                            the circuit        average current     the circuit        capacitive
                                                                                               value                                  reactance
                  In electric circuit schematics, a transformer is          A                  B                   C                  D
12   1497   A     represented by which of the symbols shown in the                                                                                           EL-0059
                  illustration?
                  Decreasing the power source frequency in a capacitive decrease the       not have any            increase the       not have any
                  circuit will __________.                              average current in affect on the           average current in affect on the
12   1498   A
                                                                        the circuit        average current         the circuit        capacitive
                                                                                           value                                      reactance
                  In the generator shown in the illustration, which     A                  B                       C                  D
12   1499   D     conductor has the maximum voltage being induced?                                                                                           EL-0029

                                                                              116                                                   Electrical Questions-April 2009
Bk   Num    Ans                          Question                              Answer A          Answer B                     Answer C             Answer D          Illustr
                  Which of the following conditions indicates a short     The capacitor      The reading is              The capacitor        The pointer moves
                  circuited capacitor when checking its condition with an shows charging,    practically zero            shows no charging    quickly to the low
                  ohmmeter?                                               but the final      and remains there.          action, but          resistance side of
                                                                          resistance reading                             indicates a very     the scale, then
12   1500   B                                                             is appreciably                                 high resistance.     slowly recedes
                                                                          more than normal.                                                   toward infinity.



                  A shorted armature coil in a DC motor can be detected        sparking at the      shiny armature coil worn grooves in       undercut mica
12   1504   A
                  by __________.                                               brushes                                  the armature
                  What would be the total current in the circuit illustrated   27 amps              37 amps             47 amps               57 amps
                  if the value of capacitor A was 100 microfarads,
12   1505   A                                                                                                                                                       EL-0038
                  capacitor B was 200 microfarads and the power supply
                  was 240 volts at 60 Hz?
                  Which of the following precautions should be taken           Never use this       Always remember      Never connect the    Always pre-set the
                  when troubleshooting various power circuits using a          tester on circuits   that the unit is     device to circuits   meter to the next
                  VOM multimeter?                                              greater than 60 Hz   polarity sensitive   where potentials     higher range than
                                                                               as the tester may    and if used on DC    greater than 120     the amount of
                                                                               not register         circuits reversing   volts may be         voltage expected
                                                                               voltages over 60     the leads may        present, as the      in the circuit in
12   1506   D                                                                  Hz.                  result in high       coil's extremely     order to prevent
                                                                                                    temperatures         fine wire cannot     damage from an
                                                                                                    within the tester.   withstand more       off-scale reading.
                                                                                                                         than a few amps.



                  Which of the following statements is true concerning         The circuit is     The controller is      The controller is    Depressing both
                  the motor controller circuit shown in the illustration?      configured for Low configured for use     configured for use   the forward and
                                                                               Voltage Release. with a                   with a three phase   reverse buttons
12   1507   C                                                                                     synchronous            reversible motor.    simultaneously,       EL-0004
                                                                                                  single phase                                will cause a
                                                                                                  reversible motor.                           control circuit
                                                                                                                                              overload.
                  In the illustrated one line diagram, if the turbo            will automatically   will automatically   will automatically   must be manually
                  generator fails, the diesel generator __________.            start and supply     start and supply     start but the        started but once
                                                                               power to the         power to the         automatic bus        running will supply
                                                                               emergency power      emergency power      transfer equipment   power to the
                                                                               switchboard, the     switchboard and      must be manually     lighting main
12   1508   B                                                                  power distribution   the lighting main    shifted to           through the ABT       EL-0014
                                                                               panel, and the                            'Emergency
                                                                               lighting main                             Power' to supply
                                                                                                                         the lighting main


                                                                                 117                                                    Electrical Questions-April 2009
Bk   Num    Ans                          Question                                     Answer A              Answer B           Answer C           Answer D             Illustr
                  Coast Guard Regulations (46 CFR Part 112) state that           radios installed in   portable radios for emergency power emergency gas
                  a continuous trickle charge, supplied from the ship's          the lifeboats         the lifeboats       systems for radar turbine generator
12   1509   D
                  service power system, is required for batteries                                                                            starting system
                  supplying power to the __________.
                  Which of the following statements concerning nickel-           Nickel-cadmium        Nickel-cadmium       The electrolyte of   When mixing
                  cadmium batteries is true?                                     batteries are less    batteries should     an idle nickel-      electrolyte always
                                                                                 susceptible to        only be discharged   cadmium battery      add acid to the
                                                                                 local action than     50% before           must be replaced     water.
12   1510   A                                                                    lead-acid             recharging.          monthly to
                                                                                 batteries.                                 maintain battery
                                                                                                                            condition.

                  A battery is connected to a circuit containing three           2 volts               6 volts              12 volts             24 volt
                  resistors in parallel. The values of the three resistors
12   1511   C     are 2 ohms, 3 ohms, and 6 ohms. What is the voltage
                  of the battery if the total circuit current is 12 amps?

                  In the illustration, if the device in figure "A" has a step-   0 volts               110 volts            550 volts            1100 volts
                  up ratio of 5 to 1 and is connected to 110 volts DC
12   1512   A     instead of 110 volts AC, the continuous voltage                                                                                                     EL-0059
                  measured at the secondary of the device will be
                  __________
                  When two generators are on the line and are sharing            frequency             series               parallel             resonance
12   1513   C     the load equally, they are said to be operating in
                  __________.
                  As shown in the illustration, the purpose of the items         statically balance    axially position the dynamically          cool the stator
12   1515   B     labeled 3B, 4C, 4E, and 4D is to __________.                   the rotor             rotor                balance the rotor                         EL-0001

                  What is the rotor speed of a six pole, 60 cycle,               3492 RPM              1800 RPM             1164 RPM             1746 RPM
12   1516   C     induction motor operating at full load with 3% slip?

                  The diagram shown in the illustration represents a/an          step-up               magnetic amplifier autotransformer      Scott-connected
12   1517   A                                                                                                                                                         EL-0082
                  __________.                                                    transformer                                                   transformer
                  From the illustration shown, what can be determined            Generator A has a     Percent speed        The percent speed Both generators
                  from the speed droop characteristics of generator A            greater speed         droop for            droop is equal for cannot be
                  and generator B?                                               droop value than      generator B is       both machines at paralleled due to
12   1518   B                                                                    generator B           8.7%                 62 % load          their different        EL-0025
                                                                                                                                               speed droop
                                                                                                                                               values
                  Which of the following statements concerning the               The symbol            The switch           The switch           The symbol
                  illustration is true?                                          illustrates a         functions as an      functions with       illustrates an
12   1519   C                                                                                                                                                         EL-0026
                                                                                 computer cable        analog logic         binary logic         overload relay.
                                                                                 pin plug.             controller.

                                                                                   118                                                       Electrical Questions-April 2009
Bk   Num    Ans                            Question                               Answer A           Answer B            Answer C                 Answer D          Illustr
                  For practical purposes, in a simple series circuit         a resistance equal half the resistance at least ten times       a partial short
                  employing two resistors, a drop of one half the source     to the other       value of the other the resistance of         circuit
12   1520   A
                  voltage will occur across one resistor if it has                              resistor            the other
                  __________.
                  The formula for computing impedance in a series            Z = RT + XL + XC Z = R + XL - XC         Z * Z = R * R + (XL Z = R * R + (XL *
                  circuit containing resistance, capacitance, and                                                     - XC) * (XL - XC) XC) - (XL * XC)
12   1521   C
                  inductance is __________. [ NOTE: the symbol *
                  stands for 'multiplied by' ]
                  For practical purposes, in a simple series circuit         a partial short     the greatest         a resistance equal less resistance
                  employing two resistors, the largest voltage drop will     circuit             resistance           to the other       than the other
12   1522   B
                  occur across the resistor which has __________.                                                                        resistor

                  Prior to closing the circuit breaker when paralleling two voltage of the       frequency of the     synchroscope           current from the
                  DC generators, you must be certain that the               incoming machine     incoming machine     needle is revolving    incoming machine
                  __________.                                               is at or slightly    is slightly higher   slowly in the 'fast'   is the same as the
12   1523   A                                                               above the bus        than the bus         direction              bus current
                                                                            voltage              frequency

                  A short in the shunt field of a DC motor is best located visual inspection applying AC              using a growler        isolating each coil
                  by __________.                                           of the commutator voltage to each          and hacksaw            from the others
                                                                                             field coil and           blade                  and using a
12   1524   B                                                                                measuring the                                   megohmmeter
                                                                                             voltage drop
                                                                                             across each field
                                                                                             coil
                  The symbol shown as figure "A" represents a/an             transformer         coil                 shunt field            inductor
12   1527   A                                                                                                                                                      EL-0059
                  __________.
                  In the illustration shown, when is the solenoid valve        Whenever a        When the "energy Only when the ice All of the above.
                  installed?                                                   backpressure      saving" mode is  maker option is
12   1528   C                                                                                                                                                      EL-0043
                                                                               regulator is      present.         installed.
                                                                               present.
                  In the illustration shown, the electrical power supply       compressor        "L1" and "L2"        energy saver       "PTC" relay
12   1529   B     originates at the __________.                                capacitor         terminal block       switch connections terminal board            EL-0043
                                                                               connector block
                  In the illustration, if the device in figure "A" has a step- 0 volts           11 volts             110 volts              1100 volts
                  up ratio of 10 to 1, what voltage should be measured at
12   1530   D                                                                                                                                                      EL-0059
                  the secondary if the primary is connected to 110 volts
                  AC?
                  In a three-wire, 230/115 volt DC system, the potential 0 volts                 115 volts            230 volts              460 volts
12   1531   B     between neutral and negative is __________.



                                                                               119                                                      Electrical Questions-April 2009
Bk   Num    Ans                            Question                             Answer A           Answer B                   Answer C              Answer D          Illustr
                  The main difference between a motor control circuit       normally open line thermal-overload          a maintained-         a momentary-
                  containing low voltage protection and low voltage         contacts           protection                contact start         contact start
12   1532   C
                  release is that the latter contains __________.                                                        button                button

                  Which of the following precautions should be taken        Never use this          Always remember      Never connect the     Always check a
                  when troubleshooting various power circuits using an      tester on circuits of   that the unit is     device to circuits    known power
                  electronic voltage tester?                                60 Hz, as the           polarity sensitive   where potentials      source of the
                                                                            tester may not          and if used on DC    are greater than      same type and
                                                                            register the            circuits reversing   120 volts.            voltage before
12   1535   D                                                               voltage.                the leads may                              using it to
                                                                                                    result in high                             troubleshoot
                                                                                                    temperatures                               electrical
                                                                                                    within the tester.                         equipment.



                  What type of electrical control diagram is shown in the   wiring diagram          schematic diagram one line diagram         logic diagram
12   1536   A                                                                                                                                                        EL-0023
                  illustration?
                  What is represented by the electric symbol figure "D"     Fuse                    Plug-in contact   Variable capacitor Electrolytic
12   1537   A                                                                                                                                                        EL-0005
                  in the illustration?                                                              resistor                             capacitor
                  What type of electrical control diagram is shown in the   logic diagram           schematic diagram one line diagram wiring diagram
12   1538   B                                                                                                                                                        EL-0007
                  illustration?
                  What type of electrical control diagram is shown in the   schematic diagram wiring diagram             logic diagram         one line diagram
12   1539   C                                                                                                                                                        EL-0089
                  illustration?
                  Which of the following statements concerning Nickel-      When mixing Ni-         When mixing Ni-      Nickel-Cadmium        The electrolyte of
                  Cadmium batteries is true?                                Cad electrolyte         Cad electrolyte      batteries can be      an idle Nickel-
                                                                            always add acid to      always add water     stored for a long     Cadmium battery
                                                                            the water.              to the acid.         period of time        must be replaced
12   1540   C                                                                                                            while still keeping   monthly to
                                                                                                                         a full charge.        maintain battery
                                                                                                                                               condition.

                  An electrical component is connected across a 120 volt 0.01 amperes               0.60 amperes         1.67 amperes          100 amperes
                  60 hertz AC supply. What is the current drawn by the
12   1541   B
                  component if the impedance is 200 ohms?

                  When rolling over a DC main propulsion motor in local to the fast position a sufficient amount quickly to the mid            quickly to the fast
                  emergency or throttle bypass mode, the variable       until the armature to assure armature position to                      position
                  rheostat must FIRST be turned __________.             begins to rotate     rotation            energize the field
12   1542   B                                                           and then turned
                                                                        back to slow



                                                                              120                                                        Electrical Questions-April 2009
Bk   Num    Ans                          Question                              Answer A            Answer B             Answer C            Answer D           Illustr
                  Which of the methods listed is used to maintain the     The shunt fields    The shunt field      The series fields ofThe equalizer
                  division of load between two compound-wound, DC         are                 rheostats are        both generators     connection
12   1543   D     generators operating in parallel?                       interconnected.     interconnected.      are connected in    parallels the series
                                                                                                                   series.             fields of all
                                                                                                                                       machines.
                  Which of the following statements is true concerning    The rotor follows The silicon-          The source and       The cyclo-
                  the operation of modern marine electric drive DC        the frequency and controlled rectifiers load converters      converter is used
                  propulsion motors?                                      phase sequence in the power             respond to a small to increase the
                                                                          rotation of voltage converter are used reference voltage voltage applied to
                                                                          applied to the      to control the      increasing the       the motor until it
12   1544   B                                                             motor until it      voltage and         frequency applied reaches the
                                                                          reaches the         current applied to to the motor until it desired speed.
                                                                          desired speed.      the motor           reaches the
                                                                                              armature.           desired speed.



                  A carbon resistor which is color coded as red, violet,  1%                  5%                   10%                    20%
                  brown, and silver in bands A thru D respectfully, would
12   1545   C                                                                                                                                                 EL-0103
                  indicate a tolerance of __________.

                  A carbon resistor has a resistance of 50 ohms, and a    gray, black, brown, green, black,        gray, black, brown, green, black,
                  tolerance of 5 percent. What would be the respective    and silver.         black, and silver.   and gold.           black, and gold.
12   1546   D                                                                                                                                                 EL-0103
                  colors indicated for bands A, B, C and D for this
                  resistor?
                  As shown in the illustration, "B" is a __________.        single-pole, double- double-pole, single- double-pole,       circuit breaker
12   1547   C                                                               throw switch         throw switch         double-throw                            EL-0058
                                                                                                                      switch
                  A carbon resistor has the following color bands; Band 74 ohms + or - 5% 4700 ohms + or - 74,000 ohms + or - 470,000 ohms + or
12   1548   D     A is yellow, followed by violet, yellow, and silver. What                      10%                  5%                 - 10%                EL-0103
                  is the value of the resistor in ohms?
                  What would be the ohmic value of a carbon resistor if 42.75 to 47.25           4,275 to 4,725       42,750 to 47,250 427,500 to
12   1550   C     the color bands A, B, C, and D were yellow, green,        ohms                 ohms                 ohms               472,500 ohms         EL-0103
                  orange, and gold respectively.
                  A carbon resistor operating in electrical equipment that change its value      increase its         decrease its       always operate at
                  is NOT properly cooled will __________.                   inversely            reliability factor   reliability factor the same ohmic
                                                                            proportional to the                                          value
12   1552   C                                                               amount of heat
                                                                            generated and
                                                                            time in service

                  A carbon resistor has the following color bands; Band   47 ohms + or -      7400 ohms + or -     47,000 ohms + or - 740,000 ohms + or
12   1553   C     A is yellow, followed by violet, orange, and silver.    10%                 5%                   10%                - 5%                    EL-0103
                  What is the ohmic value of the resistor?

                                                                            121                                                    Electrical Questions-April 2009
Bk   Num    Ans                            Question                                Answer A          Answer B                   Answer C           Answer D                Illustr
                  A carbon resistor has the following color bands; Band        47 ohms + or - 5% 7400 ohms + or -           47,000 ohms + or - 740,000 ohms + or
12   1554   A     A is yellow, followed by violet, black, and gold. What is                      10%                        5%                 - 10%                      EL-0103
                  the ohmic value of the resistor?
                  A carbon resistor has the following color bands; Band        4.7 ohms + or -         47 ohms + or - 5% 4700 ohms + or -          4.7 K ohms + or -
12   1555   A     A is yellow, followed by violet, gold, and silver. What is   10%                                       10%                       5%                     EL-0103
                  the ohmic value of the resistor?
                  While on watch in the engine room, you are setting up        The breaker             The breaker          The frequency          A portable phase
                  to parallel alternators. The switchboard has a               should be closed        should be closed     meter should be        sequence
                  synchroscope and synchronizing lamps. If the                 when one                when both            used to determine      indicator must be
                  synchoscope is broken, which of the steps listed is the      synchronizing           synchronizing        that the incoming      used to verify the
12   1556   C     most essential before an alternator can be paralleled        lamp is dark and        lamps are bright.    alternator             information from
                  with the bus?                                                the other is bright.                         frequency is           the lamps.
                                                                                                                            slightly higher than
                                                                                                                            the bus.

                  While paralleling two alternators, the synchronizing         incoming                alternator voltages synchroscope is         alternator power
                  lamps remain lit as the synchroscope pointer                 alternator is           are equal           defective or            factors are in
12   1558   C
                  approaches the 0°. This would indicate that                  running too fast                            broken                  phase
                  the__________.
                  Which of the following statements is correct regarding       It must be              You should always    The indicating         An external shunt
                  the use of a multimeter when directly measuring              connected in            start with the       needle is deflected    is generally
                  current?                                                     series with the         lowest range until   from left to right     utilized where
12   1559   A                                                                  circuit.                a suitable reading   regardless of          current is less than
                                                                                                       is obtained.         polarity.              10 amperes.

                  In the illustration, the diode between terminals 16 andinsure that the               compensate for       protect the            act as a filter to
                  17 is to __________.                                   voltage across the            the temperature      electronic             prevent hunting
12   1560   C                                                            governor coil (EG-            difference of the    governor circuits                             EL-0046
                                                                         3P) never exceeds             governor oil         from reverse
                                                                         .6 VDC                        heating up           polarity currents
                  A lamp has a source voltage of 110 volts and a current 0.008 ohms                    0.08 ohms            12.22 ohms             122.22 ohms
12   1561   D     of 0.9 amps. What is the resistance of the lamp?

                  Which of the following precautions should be taken           Never use this          Always remember      Never connect the      Always verify that
                  when troubleshooting various power circuits using an         tester on circuits of   that the unit is     device to circuits     the power source
                  electronic solenoid type voltage tester?                     60 Hz, as the           polarity sensitive   where potentials       frequency is
                                                                               tester may not          and if used on DC    are greater than       compatible with
                                                                               register the            circuits reversing   120 volts.             the instrument
12   1562   D                                                                  voltage.                the leads may                               before using it to
                                                                                                       result in high                              troubleshoot
                                                                                                       temperatures                                electrical
                                                                                                       within the tester.                          equipment.



                                                                                 122                                                        Electrical Questions-April 2009
Bk   Num    Ans                          Question                                  Answer A         Answer B             Answer C           Answer D         Illustr
                  Which of the listed conditions might contribute to very      A grounded       Using improper      Aligning the front An open circuit in
12   1564   B     rapid wearing of a DC machine's commutator bars?             commutator bar   grade of carbon     and rear mica V- the armature
                                                                                                brushes             rings improperly
                  With regard to the maintenance of electrical generating touch the bearing     use a megohm        paint or allow     All of the above
                  machines with pedestal insulated bearings it is         shell while the       meter with the      grease build up on
                  important to never __________.                          machine running       machine             the insulated area
12   1566   C                                                                                   disassembled to
                                                                                                determine
                                                                                                insulation values
                  If only fuse #2 shown in the illustration is defective, a show a reading of show full line        show the same      show a reading of
                  voltage tester connected across points "C" and "D" will 55 volts            voltage               voltage when       zero volts
12   1568   B     __________.                                                                                       connected to                            EL-0062
                                                                                                                    points "B" and "D"

                  If only fuse #1 shown in the illustration is defective, a show a reading of show full line        show the same      show a reading of
                  voltage tester connected across points "A" and "D" will 55 volts            voltage               voltage when       zero volts
12   1569   B     __________.                                                                                       connected to                            EL-0062
                                                                                                                    points "B" and "D"

                  If only fuse #1 shown in the illustration is defective, a show a reading of show full line        show the same      show a reading of
                  voltage tester connected across points "B" and "C" will 55 volts            voltage               voltage when       zero volts
12   1570   D     __________.                                                                                       connected to                            EL-0062
                                                                                                                    points "B" and "A"

                  A coil is wound with 200 feet of No. 16 tinned copper    1.14 amps         7.04 amps              10.22 amps         14.08 amps
                  wire and connected to a 12 volt battery. What is the
12   1571   D
                  current if the resistance per 1000 feet of No. 16 tinned
                  copper wire is 4.26 ohms?
                  Component 'CR1' shown in the illustration is called      Voltage reference Zener diode            Reverse            all of the above
12   1572   D     a/an __________.                                         diode                                    breakdown voltage                       EL-0085
                                                                                                                    diode
                  If a D.C. motor does not run when energized, which of        Incorrect lead   Incorrect brush     A dirty commutator All of the above
12   1573   D
                  the listed conditions could exist?                           connections      setting                                are correct.
                  When a megohmmeter is used to test the winding               an open in the   weak batteries in   the absence of     the capacitance of
                  insulation of a large motor, an initial dip of the pointer   winding being    the meter           current along the the winding
12   1574   D
                  toward 'zero' is caused by __________.                       tested                               surface of clean
                                                                                                                    insulation
                  As shown in the AC electrical system power triangle,         A divided by B   A divided by C      B divided by A     B divided by C
12   1575   D     which value represents the power factor for the                                                                                           EL-0105
                  system?


                                                                                123                                                Electrical Questions-April 2009
Bk   Num    Ans                          Question                              Answer A             Answer B             Answer C        Answer D           Illustr
                  What is the significance of having an indicated power   The generator        80% of the energy   80% of the output This information
                  factor of 0.8 when describing the output of a           output voltage and   input to the        will be converted characterizes the
12   1576   C     generator?                                              current can be       generator           to useful power.  DC output of the
                                                                          described as 20%     produces useful                       generator.
                                                                          resistive.           output.
                  If fuse #1 shown in the illustration is defective, a    show a reading of    show full line      prove that fuse #2 show a reading of
12   1577   D     voltage tester connected across points "C" and "B" will 55 volts             voltage             is good            zero volts           EL-0062
                  __________.
                  The term "volt" describes __________.                   a rate of electron   the resistance to   an electrical       the transfer of
12   1578   C                                                             flow.                current flow.       potential           circulating
                                                                                                                   difference.         currents.
                  A 4160 Volt AC generator is loaded to 2850 kW with a     503 kVAR            1766 kVAR           2850 kVAR           3353 kVAR
12   1579   B     0.85 power factor. What is the approximate kVAR load
                  on the generator?
                  A 120 volt battery is rated at 800 amp-hours for a       60 minutes          75 minutes          90 minutes          115 minutes
                  continuous 50 kW load. Approximately how long will
12   1580   D     the fully charged battery be able to supply a
                  continuous 50 kW load before the battery rating is
                  exceeded?
                  The prime mover of an AC two pole main propulsion        45 RPM              80 RPM              90 RPM              180 RPM
                  generator drives the generator at 3600 RPM. If the
12   1581   C
                  main propulsion motor has 80 poles, what will be the
                  propeller speed?
                  If the field current of a paralleled AC generator is     VAR's will          VAR's will          VAR's will          VAR's will
                  increased above normal, what will be the net result to   increase and the    increase and the    decrease and the    decrease and the
12   1582   A     the VAR's and power factor?                              power factor will   power factor will   power factor will   power factor will
                                                                           be more lagging     be more leading     be more lagging     be more leading

                  If the field current of a paralleled AC generator is     VAR's will          VAR's will          VAR's will          VAR's will
                  increased above normal, what will be the net result to   increase and the    increase and the    decrease and the    decrease and the
12   1584   B     the VAR's and power factor?                              power factor will   power factor will   power factor will   power factor will
                                                                           be more leading     be more lagging     be more lagging     be more leading

                  If the field current of a paralleled AC generator is     VAR's will          VAR's will          VAR's will          VAR's will
                  increased above normal, what will be the net result to   decrease and the    increase and the    decrease and the    increase and the
12   1585   D     the VAR's and power factor?                              power factor will   power factor will   power factor will   power factor will
                                                                           be more leading     be more leading     be more lagging     be more lagging

                  On some diesel-electric ships, the DC propulsion         raising the         rotating brush      decreasing          lowering the
                  motor will only attain half speed when the generator     generator engine    alignment           excitation          generator engine
12   1586   A
                  fields are fully excited. Speeds above this are          speed                                                       speed
                  obtained by __________.

                                                                             124                                                   Electrical Questions-April 2009
Bk   Num    Ans                             Question                                Answer A               Answer B            Answer C                Answer D            Illustr
                  When three-phase AC power is supplied to the device          single-phase AC        split-phase AC       three-phase DC          unidirectional DC
12   1587   D     shown in the illustration, the output will be                                                                                                           EL-0063
                  __________.
                  When two generators are operating in parallel, what          Generator #1         Generator #1           Generator #2 will       Generator #2
                  will first occur if the engine driving generator #1          circuit breaker will circuit breaker will   motorize.               engine will
12   1588   B
                  suddenly loses power?                                        trip on overload.    trip on reverse                                automatically shut
                                                                                                    power.                                         down.
                  An AC generator operating in parallel loses its              not affect the       cause the slip         increase the            cause high
                  excitation without tripping the circuit breaker. This will   faulty generator     rings to melt          output amperage         currents to be
                  __________.                                                  due to the                                  between the             induced in the field
12   1590   D                                                                  compensation of                             armature and the        windings
                                                                               the other                                   bus
                                                                               generators
                  A coil is wound with 400 feet of No. 16 tinned copper    4.8 amps            7.04 amps         10.65 amps                        11.27 amps
                  wire and connected to a 12 volt battery. What is the
12   1591   B
                  current if the resistance per 1000 feet of No. 16 tinned
                  copper wire is 4.26 ohms?
                  The recommended method used to resurface an              turn it down in the use a hard canvas use a hand stone burnish it with
12   1592   A     eccentric DC motor commutator is to __________.          ship's lathe        wipe                               commutator
                                                                                                                                  stones
                  Sparking at the brushes of a running motor could be an normal operation a dirty commutator increased brush      water vapor
12   1594   B
                  indication of __________.                                                                    capacity           absorption
                  Which of the following statements is true concerning   The alternator      The alternator    The alternator     The alternator
                  the following illustration?                            voltage is higher   frequency is      frequency is lower frequency is equal
12   1595   B                                                                                                                                                             EL-0002
                                                                         than the line       higher than the   than the line      to the line
                                                                         voltage.            line frequency.   frequency.         frequency.
                  Which of the following statements is true concerning   The line frequency The line frequency The line frequency The line frequency
                  the following illustration?                            is greater than the is 1/4 of the     is 2/3 of the      is 3/4 of the
12   1596   D                                                            alternators         alternators       alternators        alternators                             EL-0002
                                                                         frequency.          frequency.        frequency.         frequency.

                  Regarding an induction motor, the output power               speed of the           slip of the rotor    current flow in the     DC field excitation
12   1597   B
                  developed is related to the __________.                      rotating field                              interpoles
                  What common shipboard system does figure "B"                 Navigational           Rudder angle         Sound powered           Winch speed
12   1598   B                                                                                                                                                             EL-0092
                  represent?                                                   running lights         indicator            telephone               control
                  While standing an "at sea watch" onboard a DC diesel-        check the              notify the bridge    send the oiler to       reduce load by
                  electric drive ship you notice the transformer core          transformer            that you need to     look for fires in the   tripping lighting
12   1599   A     temperature slowly rising. You should first                  ventilation fans for   slow down            transformer             circuits
                  __________.                                                  proper operation

                  A three-phase alternator operates at 450 volts with a        90.00 KW               127.27 KW            155.70 KW               194.85 KW
                  0.8 power factor. If the ammeter indicates 250
12   1601   C
                  amperes, what should be the KW meter reading?

                                                                                 125                                                        Electrical Questions-April 2009
Bk   Num    Ans                         Question                                 Answer A             Answer B           Answer C                 Answer D          Illustr
                  The difference between the synchronous speed of a          a percent of full   a decimal fraction slip                     all of the above
                  three phase induction motor and its operating speed        load speed          of full load speed
12   1602   C
                  may be correctly expressed as ________.

                  Electrical failures in motors are caused by the            penetration of      accumulation of        overheating          all of the above
12   1604   D     breakdown of insulation, which may be caused by            moisture            dirt
                  __________.
                  The safest time to close the ships main switchboard        only after the      at any time in a       if a quick           when the ship's
                  "shore power" circuit breaker would be __________.         ship's generators shipyard                 disconnect           generators have
                                                                             have been directly                         coupling is used     been deenergized
12   1605   D                                                                paralleled to those                                             from the main bus
                                                                             on shore

                  In the illustrated electronic governor, the circuit card   sending a low       providing an           shutting down the    conditioning the
                  connected to the potential and current transformers is     voltage signal to   electronic signal to   prime mover if the   load through the
                  for __________.                                            the voltage         the engine             output circuit       use of a magnetic
12   1606   A                                                                regulator           governor to            breaker trips        amplifier current     EL-0046
                                                                                                 maintain proper                             transformer
                                                                                                 load sharing and
                                                                                                 speed control
                  What current is required to light two 75 watt lamps and 0.161 amperes          0.631 amperes          1.583 amperes        6.199 amperes
12   1607   C     one 40 watt lamp when connected in parallel to a 120
                  volt power source?
                  Upon failure of the ships normal electrical power       main lighting          automatic bus          main switchboard     power failure
                  supply, the emergency generator should automatically transformer               transfer switch        bus                  alarm bus
12   1608   B     start and supply power to the emergency switchboard
                  through the __________.

                  You are in the process of paralleling two AC               the frequency of    the incoming           the circuit breaker there is an existing
                  generators and the synchroscope pointer has stopped        the incoming        machine is in          needs to be reset cross current
                  at a position other than 0°. This indicates that           machine is the      phase with the                             between
12   1609   A     __________.                                                same as the bus     bus, but the                               generators
                                                                             frequency           frequency is not
                                                                                                 the same
                  From the information given in the illustration, what       200 Amps            350 Amps               600 Amps             1600 Amps
                  would be the maximum output amperage available
12   1610   B                                                                                                                                                      EL-0106
                  from the emergency generator if it operated with a
                  power factor of 0.9?
                  An operational amplifier, as used in today's consoles,     5 volts, the output 10 volts, the          2 volts, the output 10 volts, the
                  has a calculated gain of 5. This means that when the       changes 10 volts output changes 5          changes 10 volts output changes 2
12   1611   C
                  input changes __________.                                                      volts                                      volts


                                                                               126                                                      Electrical Questions-April 2009
Bk   Num    Ans                          Question                               Answer A                   Answer B              Answer C               Answer D         Illustr
                  From the information given in the illustration, what     0.6                       0.7                   0.8                    0.9
12   1612   C     would be the approximate designed rated power factor                                                                                                  EL-0106
                  of the main ship service turbo generators?
                  From the information given in the illustration, which of The emergency             Shore power does      The emergency       All of the above
                  the following statements is correct?                     generator does not        not normally          bus tie circuit
12   1615   A                                                              normally supply           supply the 230 volt   breaker is rated at                          EL-0106
                                                                           the 230 volt              distribution.         1200 amps.
                                                                           distribution.
                  From the information given in the illustration, which of Automation should         A interlock           The emergency      All of the above
                  the following statements is correct?                     automatically start       prevents circuit      generator output
                                                                           the emergency             breaker 52N from      circuit breaker
                                                                           generator and             being closed when     would not normally
                                                                           close circuit             the emergency         be expected to
12   1616   D                                                              breaker 52E if            generator is on       carry more than                              EL-0106
                                                                           circuit breaker 52N       line.                 400 amps.
                                                                           is manually tripped
                                                                           open.



                  Voltage will always lead current in a/an __________.         capacitive circuit    inductive circuit     direct current         resistive circuit
12   1617   B
                                                                                                                           circuit
                  What will be the frequency of a three-phase, 16 pole,        60 hertz              90 hertz              180 hertz              400 hertz
12   1619   D     AC generator operating at 3000 revolutions per
                  minute?
                  When testing the rotor of a synchronous motor for            high voltage drop     low or zero voltage   fluctuating            steady voltmeter
                  short circuits, a low voltage source is applied across       reading, while the    drop reading,         voltmeter reading,     reading, while the
                  the rotor coils through the collector rings. A coil having   other coil readings   while the other       while the other coil   other coil readings
12   1620   B     a short circuit will be indicated by a _______.              will have an equal    coils will have       readings are           are fluctuating
                                                                               or lower value        higher readings       steady

                  If the synchronous speed of a 12 pole, polyphase,            4                     6                     8                      18
                  induction motor operating at 60 Hz were 600 RPM,
12   1621   C     how many poles will be required in a similar motor
                  operating at the same frequency but having a
                  synchronous speed of 900 RPM?
                  A magnetic relay is most commonly used to                    provide inductive     remotely open and provide           provide
                  __________.                                                  power to a circuit    close contacts    transformer       capacitance to a
                                                                                                                       secondary winding circuit
12   1622   B                                                                                                          overcurrent
                                                                                                                       protection

                  If a single-phase induction motor fails to start, the        an open in the        a shorted shunt       a closed               low circuit
12   1624   A     problem may be __________.                                   main winding          field                 centrifugal switch     frequency

                                                                                   127                                                      Electrical Questions-April 2009
Bk   Num    Ans                           Question                             Answer A             Answer B            Answer C            Answer D              Illustr
                  One method of providing an input speed signal for an     small generator      bimetallic sensing stroboscopic liquid shaft torque
12   1625   A     electric analog tachometer on an engine control panel    mounted on the       device             crystal display     indicator
                  would be by using a __________.                          engine
                  A load is connected to the secondary of a power          1 amp                10 amps               100 amps             1000 amps
                  transformer and the current through the load is 10
12   1626   C     amps. If the transformer has a step-up ratio of 10 and
                  the input voltage to the primary is 110 VAC, what will
                  be the current flow through the primary?
                  When charging a 100 amp-hour lead-acid battery,          the temperature of   the charging rate     the source of      always start with a
                  __________.                                              the electrolyte      should be no          power for charging trickle charge rate
                                                                           should not be        greater than 125%     should be
12   1627   C                                                              allowed to exceed    of the battery amp-   approximately 2.5
                                                                           90°F                 hour rating           volts per cell

                  A 125 volt DC motor is rated at 10 kW. What is the       4.6 amps             8.0 amps              46.2 amps            80 amps
12   1628   D
                  current rating of the motor?
                  The difference between the synchronous speed of an       a percent of         the reduced amp       the decrease in      all of the above
                  three phase induction motor and its operating speed is   synchronous          rating                shaft torque
12   1629   A
                  called slip and may be correctly expressed as            speed
                  __________.
                  Which of the listed types of lighting circuits is        Standard             Low voltage quartz Liquid crystal          Standard
12   1630   D                                                                                                                                                    EL-0081
                  illustrated in the diagram shown?                        incandescent                            display                 fluorescent
                  A four-pole, 60 cycle, squirrel-cage motor has a full    4.16                 4.34               95.66                   95.84
12   1631   A     load speed of 1725 RPM. What will be the percent of
                  slip at full load?
                  Which of the meters listed should only be used after a   Wattmeter            Frequency meter       Ammeter              Ohmmeter
12   1632   D
                  circuit has been electrically deenergized?
                  A single-phase induction motor starts, comes up to       starting winding     running winding       starting capacitor   running centrifugal
                  about 75% rated speed, slows down to a lower speed,                                                                      switch
12   1634   B
                  and accelerates again. The problem is most likely in
                  the __________.
                  The circuit power factor of an AC generator operating    connected load       prime mover           ground current       generator's rated
12   1635   A     singularly is determined by the __________.                                   speed                                      voltage

                  When a fluorescent lamp has reached the end of its       blow the lamp's      explode, causing      short circuit        damage the lamps
                  useful life, it should be replaced immediately, or the   circuit breaker      glass to fly in all   adjacent lighting    starter and ballast
12   1637   D
                  resultant flashing may __________.                                            directions            circuits             circuit

                  Voltage generated by modern revolving field AC       brushes on a             brushes on slip       slip rings on a      direct connections
12   1638   D     generators is fed to the bus by means of __________. commutator               rings                 commutator           from the stator



                                                                             128                                                        Electrical Questions-April 2009
Bk   Num    Ans                        Question                                      Answer A             Answer B             Answer C              Answer D       Illustr
                  Engine RPM can be indicated on a engine control               small engine          bimetallic sensor   ultraviolet radiation shaft torque
                  panel by measuring the voltage from a ________.               driven signal         mounted in the      counter               indicator
12   1639   A
                                                                                generator             exhaust manifold                          transducer

                  Capacitors are commonly used on power supply                  filter out 'ripple'   prevent overloads act as a              decrease the
                  circuits for engine room automation consoles to               from rectification                      permanent load        average value of
12   1640   A
                  __________.                                                                                                                 the output voltage

                  Electric motors intended for use outside the engine           54.2°F                72.0°F              104.0°F             129.6°F
                  room and boiler room are frequently rated to run at a
12   1641   C     designed ambient temperature of 40°C. What is the
                  equivalent temperature in degrees Fahrenheit?

                  To properly seat the brushes on a commutator or slip          sand paper            crocus cloth        diamond file        hack saw
12   1642   A
                  rings, you should use __________.
                  Which of the following statements, concerning the             Paint should be       Hot soapy water     High pressure air   Accessible
                  general maintenance of a brushless generator, is              applied to            should be used to   should be used to   generator parts
                  correct?                                                      insulating surfaces   remove dust and     blow out carbon     should be wiped
12   1644   D                                                                   on an annual          grime from          dust.               with a clean dry
                                                                                basis.                windings.                               rag on a periodic
                                                                                                                                              basis.
                  What would be the source voltage of the circuit if the        1080 volts            30 volts            3 volts             .033 volts
12   1645   A     current flow was 6 amps and the resistance was 180                                                                                               EL-0018
                  ohms?
                  What would be the resistance value of the circuit if the      500 ohms              5 ohms              1.25 ohms           12.5 ohms
12   1646   A     current was .05 amps and the source voltage was 25                                                                                               EL-0018
                  volts?
                  What is the total resistance of the resistor circuit if the   2 ohms                0.5 ohms            1.28 ohms           12 ohms
12   1647   D     resistance of R1 is 3 ohms, R2 is 4 ohms, and R3 is 5                                                                                            EL-0020
                  ohms?
                  The 1.5 volt dry-cell batteries, when connected as            1.5 volts             3.0 volts           4.5 volts           6.0 volts
12   1648   A     shown in the illustration, would produce __________.                                                                                             EL-0070

                  Which of the following methods should be used to              Filing                Grinding            Sanding with 0000 All of the above
12   1649   C     dress the face of silver-plated motor controller                                                        sandpaper         are correct.
                  contacts?
                  When power is restored after a complete power failure,        have to be            have to be reset    restart             trip its overload
12   1650   C     the steering gear pump motor which was on-line, will          restarted                                 automatically       relays
                  normally __________.
                  A four-pole 60-hertz induction motor has a                    1728.0 RPM            1730.7 RPM          1800.0 RPM          1872.0 RPM
                  synchronous speed of 1800 RPM and a slip of 4
12   1651   A
                  percent at full load. What will be its full load speed?


                                                                                  129                                                     Electrical Questions-April 2009
Bk   Num    Ans                           Question                              Answer A            Answer B             Answer C           Answer D            Illustr
                  A useful instrument for checking 3 phase A.C. motor       hand or battery-   vibrating-reed        hook-on voltmeter- D'Arsonval iron-
12   1652   C     performance by measuring possible unbalanced              operated megger    frequency meter       ammeter probe      vane probe
                  currents is the __________.
                  The speed of a squirrel-cage, multi-speed, induction      number of          frequency to the      excitation voltage   resistance of the
12   1654   A     motor, as used aboard ship, is varied by changing the     connected poles in motor                                      rotor circuit
                  __________.                                               the stator
                  The KW load is evenly distributed between two             a balance coil     the engine            the rotor field      a interpole field
12   1655   B     alternators just placed in parallel by adjusting                             governor settings     excitation           rheostat
                  __________.
                  Ambient temperature is the __________.                    amount of          amount of             normal operating     temperature of the
                                                                            permissible        temperature           temperature, less    immediate
12   1657   D                                                               temperature rise   developed by an       the room             surroundings
                                                                                               operating motor       temperature

                  An electric motor can be designed and constructed to      short proof        ground proof          explosion proof      overload proof
12   1658   C
                  be __________.
                  The nominal open-circuit voltage of one cell of a fully   1.5 volts          2 volts               6 volts              12 volts
12   1659   B
                  charged lead-acid battery is __________.
                  The nominal open-circuit voltage of one cell of a fully   1.2 volts          1.5 volts             2.0 volts            3.0 volts
12   1660   A     charged wet cell nickel-cadmium battery is
                  __________.
                  When the length and cross sectional area of a wire are    increases nine fold increases three      remains the same decreases six fold
12   1661   C
                  both tripled, the resistance __________.                                      fold
                  A delayed-action fuse is most frequently used in which    Ships main lighting Large induction      Battery charging     Navigation light
12   1662   B
                  of the listed circuits?                                   circuits            motor circuits       circuits             circuits
                  When energizing a DC propulsion motor using "local        all the way to the to a position which   quickly to the mid   quickly to the full
                  override manual control", the variable rheostat should    full run position   initializes motor    position             run position
                  be turned __________.                                     then quickly back rotation and then
12   1663   B                                                               to slow             turned back to the
                                                                                                slow position

                  Universal motors will operate on AC or DC current, and    portable tools    large pump motors turbo electric main forced draft fans
12   1664   A
                  are generally found in __________.                                                            motors
                  The power factor of an electrical distribution system     components of the prime mover       output frequency generator's rated
12   1665   A     being supplied by a single AC generator is determined     connected load    speed                                 voltage
                  by the __________.
                  Hysteresis loss in transformers can be reduced by         laminating the     using special         using higher         using heavy gage
12   1666   B     __________.                                               core               silicon steel         voltages             wire
                                                                                               materials
                  Motorization of an AC generator is undesirable            the generator will it puts an            high voltage         all of the above
                  because __________.                                       be damaged when excessive load on        pulses may
12   1667   B
                                                                            it reverses its    the bus               damage the
                                                                            rotation                                 commutator

                                                                              130                                                      Electrical Questions-April 2009
Bk   Num    Ans                           Question                          Answer A            Answer B                         Answer C               Answer D         Illustr
                  If overloading an electric motor becomes necessary in cool the motor with hold thermal                    inject small           increase the
                  an emergency, you should __________.                  portable blowers overload relays                    amounts of CO2         residual
                                                                        and fans            open with blocks                into the windings      magnetism value
12   1668   A                                                                               of wood                         for cooling            of windings to
                                                                                                                                                   reduce eddy
                                                                                                                                                   currents

                  In a three-phase, squirrel-cage type, induction motor, current induced in application of a                laminated steel        interaction of the
                  the primary rotating magnetic field is established by the the rotor windings three-phase                  core and               magnetic field
                  __________.                                                                  voltage supply to            aluminum               caused by the
                                                                                               the stator windings          conductors in the      induced current in
12   1669   B                                                                                                               rotor                  the squirrel-cage
                                                                                                                                                   bars with the
                                                                                                                                                   magnetic field of
                                                                                                                                                   the stator
                  If many turns of an alternating current coil for a     will have a higher         will probably burn      will operate on        temperature will
12   1670   B     contactor become short circuited, the coil __________. resistance value           out immediately         reduced current        drop

                  If the total source voltage of the three-wire distribution   110.4 volts          112.2 volts             113.0 volts            114.8 volts
                  system shown in the illustration is 240 volts, what is
12   1671   D                                                                                                                                                           EL-0075
                  the voltage across load L5? [ NOTE: Kirchhoff's
                  voltage and current laws apply ]
                  DC generator voltage is decreased by __________.             increasing field     decreasing field        increasing             decreasing
12   1672   A                                                                  resistance           resistance              armature               armature
                                                                                                                            resistance             resistance
                  A motor enclosure which protects against falling liquids waterproof               drip proof              spray tight            spray proof
12   1674   B
                  is classified as __________.
                  The electric brake on an deck cargo winch functions to automatically              automatically hold      automatically          automatically
                  __________.                                              engage when the          the load if the         govern the             govern the
                                                                           winch motor              current to the          lowering speed of      hoisting speed of
12   1675   B                                                              current is reaching      machine is shut off     the load               the load
                                                                           full load

                  Which of the following statements concerning the             When necessary,      They should be          When black silver      When necessary,
                  maintenance of solid-silver contacts in relays and           they should always   filed with a fine-cut   oxide is present, it   they should be
                  auxiliary control circuits is correct?                       be dressed with a    file when               should always be       spray painted with
                                                                               wire wheel.          projections extend      removed from the       electrical shellac
12   1676   B                                                                                       beyond the              contact surface
                                                                                                    contact surface.        with coarse
                                                                                                                            sandpaper.




                                                                                 131                                                         Electrical Questions-April 2009
Bk   Num    Ans                           Question                                Answer A               Answer B               Answer C           Answer D                Illustr
                  As shown in the illustration, the normal direction of      from terminal "B"      from terminal "A"      opposite from that opposite from that
12   1677   B     electron flow through the component is __________.         to terminal "A"        to terminal "B"        in a capacitor     in a resistor               EL-0079

                  In addition to testing the calibration of a circuit breaker, changing out of   checking for              inspecting for        insure that foreign
                  maintenance should include all of the following              magnetic elements corrosion,                loose or missing      matter does not
12   1678   A     EXCEPT __________.                                           yearly            accumulation of           parts                 block tripping
                                                                                                 dirt and thermal                                element
                                                                                                 fatigue
                  Which of the following would best describe a standard D'Arsonval               Bourdon                   Zener                 SCR
12   1679   A     electric meter movement that uses a stationary
                  permanent magnet and movable coil?
                  The circuit shown in the illustration provides an            generator load    lighting distribution     circuit ground        generator
12   1680   C                                                                                                                                                             EL-0009
                  indication of __________.                                    distribution                                faults                synchronism
                  Unnecessary and frequent applications of insulating          improper heat     deficient air gap         failure of the        shorting out the
                  varnish to the generator stator windings to repair           dissipation       clearance and             rectifier assembly    line leads
12   1682   A     defective insulation will result in __________.                                eventual damage
                                                                                                 to the casing

                  As a result of a serious mechanical malfunction in one     Trip the               Trip all non-vital     Trip the              Trip all non-vital
                  of the ship's service generators operating in parallel,    malfunctioning         distribution feeder    malfunctioning        distribution feeder
                  you must secure that generator. In order to prevent a      generator's circuit    circuit breakers,      generator's circuit   circuit breakers,
                  possible overload to the remaining generator, which of     breaker and prime      remove the             breaker and           the malfunctioning
                  the following sequential courses of action should be       mover throttle trip.   remaining load on      distribution feeder   prime mover
                  taken?                                                                            the malfunctioning     circuit breakers.     turbine throttle trip,
12   1683   B                                                                                       generator and trip                           and the generator
                                                                                                    its circuit breaker                          circuit breaker.
                                                                                                    and then the prime
                                                                                                    mover throttle trip.




                  What is the main function in the use of a capacitor for    Reduce radio           Split the phase to Reduce the phase Prolong the life of
                  starting a single phase motor?                             interference           establish a rotating angle          the starting
12   1684   B
                                                                                                    magnetic field                      contacts

                  Which of the listed safety features should be provided     Installation of a An exhaust duct is          Deck drain lines      An exhaust duct is
                  in small rooms or lockers where batteries are stored?      fixed CO2 system. to be provided to           must be installed     to be provided and
                                                                                               draw air out from           and directed          led from the top of
12   1685   D                                                                                  within three inches         overboard.            the locker to the
                                                                                               of the deck.                                      open air.



                                                                               132                                                         Electrical Questions-April 2009
Bk   Num    Ans                              Question                           Answer A           Answer B                 Answer C              Answer D          Illustr
                  The most probable reason the contacts of a motor          contacts are       contacts have            shading coil is       shading coil is
                  starter or controller fail to drop out when the 'stop'    carrying excessive become welded            broken                loose
12   1686   B
                  button is depressed, is that the __________.              current            together

                  Which of the following electric motors would be the       Squirrel cage         Drip proof motors     Synchronous           Watertight motors
12   1687   D     most reliable to use on the open main deck of a           motors                                      motors
                  vessel?
                  Which of the following precautions should be taken        Always verify that    Always remember       Never connect the     Always pre-set the
                  when troubleshooting various power circuits using a       the circuits          that the unit is      device to circuits    meter to the next
                  common mechanical solenoid-type voltage tester            frequency (hertz)     polarity sensitive    where potentials      higher range than
                  (Wiggins)?                                                is compatible with    and if used on AC     greater than 120      the amount of
                                                                            the tester before     circuits, reversing   volts may be          voltage expected
                                                                            troubleshooting.      the leads may         present, as the       in the circuit in
12   1688   A                                                                                     result in high        coil's extremely      order to prevent
                                                                                                  temperatures          fine wire cannot      damage from an
                                                                                                  within the tester.    withstand more        off-scale reading.
                                                                                                                        than a few amps.



                  In a basic induction motor, rotor currents are circulated a bridge rectifier    an armature and       inductive reaction    external variable
                  in the rotor by __________.                                                     brushes               of the rotating       resistors
12   1689   C
                                                                                                                        stator field

                  The speed of a synchronous ac propulsion motor is         inversely         directly                  directly              inversely
                  __________.                                                                 proportional to the
                                                                            proportional to the                         proportional to the   proportional to the
12   1690   C                                                               frequency applied frequency applied         frequency applied     frequency applied
                                                                            to its stator     to its rotor              to its stator         to its rotor
                                                                            windings.         windings                  windings              windings
                  A circuit breaker for a 300 KW alternator is rated at     Sustained current Sustained current         Momentary             Sustained current
                  470 amperes of full continuous load. The amount of        flow of 470       flow of 500               starting load of      flow of 590
12   1691   D
                  over current allowed is 125%. Which of the following      amperes.          amperes for 10            550 amperes.          amperes.
                  conditions will trip the breaker?                                           minutes.
                  A low-voltage protection circuit as used in electric      trip circuit      trip circuit              allow the motor to    prevent the motor
                  motor starting equipment, will __________.                contactors when   contactors when           restart               from restarting
                                                                            the motor         the motor                 automatically on      automatically on
12   1692   D                                                               overspeeds due to develops a short          restoration of        restoration of
                                                                            low voltage       circuit due to low        voltage without       voltage
                                                                                              voltage                   manually resetting

                  Which of the following represents the recommended         100°F                 125°F                 165°F                 212°F
12   1693   B     maximum allowable temperature for electrolyte in a
                  lead-acid battery?

                                                                               133                                                        Electrical Questions-April 2009
Bk   Num    Ans                         Question                                  Answer A             Answer B           Answer C                  Answer D           Illustr
                  The most practical method of controlling the RPM of a      change input          vary the number of vary power factor         change the
12   1694   B     step-speed AC motor is to __________.                      voltage               poles                                        number of brushes

                  A loud buzzing noise in an AC controller is probably       poor contact with an incorrectly             a broken shading      counter EMF
12   1695   C     caused by __________.                                      the overload relay sized heater              coil

                  In the illustrated motor, roller bearings are used         of their ability to   they electrically      the shafting and      they minimize
                  because __________.                                        absorb stray          insulate the rotor     end bells do not      friction while
                                                                             electrical current    from the frame         require as close a    maintaining close
12   1696   D                                                                                      reducing cross-        tolerance to          tolerances            EL-0001
                                                                                                   currents               properly fit this     between the rotor
                                                                                                                          type of bearing       and stator
                  In the illustration, what is the function of the component Allows a greater      Prevents               Keeps the             Acts as an
                  labeled "F"?                                               amount of             electrolysis from      components 'D'        electrical
                                                                             electrolyte to be     occurring in the       and 'E' from          conductor for
12   1697   C                                                                stored in the cell.   cell.                  coming into           current to flow       EL-0031
                                                                                                                          contact with each
                                                                                                                          other
                  Accidental grounds in a shipboard electrical system        result in immediate damage circuit           overload the          damage insulation
                  must be repaired as soon as possible as they will          power outages       breakers                 ground detection      and may cause
12   1698   D
                  __________.                                                                                             system                outages

                  An open primary coil in a simple transformer will be    No voltage on the An infinite                   Low resistance        Overloaded
                  indicated by which of the listed conditions?            output of the      resistance value             value on the          secondary coil.
12   1699   A
                                                                          secondary coil.    on the secondary             primary coil.
                                                                                             coil.
                  On a main switchboard, if all three ground detection    The bulbs are      All three phases             The test switch is    The current
                  lamps burn with equal intensity when the test button is operating properly are grounded.                grounded.             transformers are
12   1700   A
                  depressed, which of the listed conditions is indicated?                                                                       shorted.

                  Protection against sustained overloads occurring in        over voltage          thermal acting trip reverse current          low voltage relay
12   1701   B     molded-case circuit breakers is provided by a/an           release                                   relay
                  __________.
                  The pitting of controller contacts can be caused by        excessive spring      insufficient contact   high ambient          all of the above
12   1702   B
                  __________.                                                pressure              pressure               temperature
                  A diesel driven emergency generator is prevented from      an electrical         an automatic           the synchronizing     the reverse current
12   1703   A     being paralleled with the ship's service generators by     interlock system      paralleling trip       oscilloscope          relay
                  __________.                                                                      switch
                  The energy consumed by an AC motor, as strictly            used to do            used to establish      lost as heat          lost in doing work
                  reactive power, is __________.                             mechanical work       the magnetic field     generated by          to turn the motor
12   1704   B
                                                                                                   of the motor           bearing friction      itself

                  As load is added to a DC shunt motor, the motor will       speed up              maintain the same slow down slightly stop
12   1705   C
                  __________.                                                                      speed
                                                                               134                                                           Electrical Questions-April 2009
Bk   Num    Ans                          Question                                Answer A              Answer B              Answer C               Answer D           Illustr
                  Undervoltage trips are frequently installed on           trip out generators   trip out generators   trip out the breaker   trip out the
                  switchboard circuit breakers to __________.              in the event of       when there is         if the generator       generator when
                                                                           severe arcing or      reversal of power     overspeeds by          there is insufficient
                                                                           sparking              in the main circuit   5%, but continues      voltage being
12   1706   D                                                                                                          to run                 delivered to
                                                                                                                                              distribution circuits



                  The purpose of having low voltage protection for an      prevent severe     protect against          prevent excessive prevent the motor
                  electric motor circuit is to __________.                 arcing or sparking reversal of power        current from         from overspeeding
                                                                                              in the main circuit      developing as it is
                                                                                                                       attempting to
12   1707   C                                                                                                          deliver its required
                                                                                                                       horsepower



                  Which of the following statements identifies the         The secondary         The secondary         The secondary          The secondary
                  difference between the primary windings and the          windings have         windings use          windings can only      windings have half
                  secondary windings of a 2:1 step-down transformer?       twice as much         smaller wires than    provide half as        as many turns as
12   1708   D                                                              resistance as the     the primary           much current as        the primary
                                                                           primary windings.     windings.             the primary            windings.
                                                                                                                       windings.
                  Which of the following statements is correct             The motor RPM at      The motor slip at     If the motor was All of the above.
                  concerning the motor performance curves and data         full load is          full load is          developing 10 HP
                  table shown in the illustration?                         approximately         approximately         its power factor
12   1709   D                                                              1737 RPM.             3.5%                  would be                                       EL-0006
                                                                                                                       approximately
                                                                                                                       0.92.
                  Which of the listed features would require a motor       Overload              Low voltage           Low voltage            Reverse current
12   1710   C     controller to be manually re-started following a power   protection            release               protection             protection
                  failure?
                  A turbo generator has a rated output of 1200 KW at 60    1.025%                1.500%                2.439%                 2.500%
12   1711   D     Hertz, with a no load frequency of 61.5 Hertz. What is
                  its speed droop?
                  Proper maintenance of a D.C. motor's commutator          side-cutting the      coating the copper applying a thin           all of the above
                  includes __________.                                     copper segments       surface with light coat of electrical
                                                                           and undercutting      machine oil for the varnish monthly
12   1712   A                                                              the mica              first four hours of
                                                                                                 operation




                                                                             135                                                       Electrical Questions-April 2009
Bk   Num    Ans                             Question                            Answer A                Answer B             Answer C               Answer D         Illustr
                  If an alternator is to be inactive for a considerable    It should be            Insulation           The brushes            The windings and
                  period of time, which of the following actions should be disconnected from       resistance           should be lifted off   collector rings
                  taken?                                                   the prime mover         readings should      the slip rings to      should be
12   1713   C                                                              and raised off its      be taken weekly to   prevent pitting of     protected with a
                                                                           bearing supports.       ensure resistance    the metal by           thin coat of grease
                                                                                                   is not               electrolytic action.   or oil.
                                                                                                   deteriorating.
                  Which of the following is a characteristic of fractional   They start with a  The short               The brushes are  They have a low
                  horsepower repulsion start motors?                         rotating stator    circuiting ring is      removed from the starting torque.
12   1714   B                                                                field.             removed from the        commutator while
                                                                                                commutator while        starting.
                                                                                                starting.
                  When a nickel-cadmium battery begins gassing while         do nothing as this add distilled water     add potassium        increase the
                  connected to the battery charging circuit, you should      is a normal        to each cell to         hydroxide to each charging rate
                  __________.                                                condition when     reduce the specific     cell to increase the
12   1715   A                                                                charging           gravity of the          specific gravity of
                                                                                                electrolyte             the electrolyte

                  When troubleshooting a lead-acid storage battery, a        comparing the         taking an open       visually inspecting taking each cell's
                  weak or dead cell is best detected by __________.          specific gravity of   circuit voltage test the electrolyte     temperature with a
                                                                             the electrolyte in    of individual cells levels of each cell calibrated mercury
12   1716   A                                                                each cell                                                      thermometer



                  Engine room watchstanders should keep a constant      low loads           exceeding            energy is wasted if residual
                  check on the loads carried by electric motors because necessitate         nameplate values full loading is not magnetism may
12   1717   B     __________.                                           frequent insulation shortens useful life utilized            increase
                                                                        cleaning

                  What is the approximate discharge voltage produced         1.25 volts            1.5 volts            2.2 volts              6.0 volts
12   1718   A     by one wet cell of a nickel-cadmium battery?

                  If a single-phase induction motor fails to start, the      an open in the run a shorted shunt         a defective            low circuit
12   1719   C     problem may be __________.                                 winding            field                   centrifugal switch     impedance

                  To determine if a stator coil on a AC generator is         ammeter               voltmeter            magneto                megger
12   1720   D
                  grounded, you should use a/an __________.
                  A vessel is equipped with two ship's service               100 kw                400 kw               500 kw                 600 kw
                  generators. Generator #1 is rated at 900 kw and
12   1721   B     generator #2 is rated at 600 kw. During parallel
                  operation, with a hotel load of 1,000 kw, what should
                  be the kw load on generator #2?

                                                                               136                                                       Electrical Questions-April 2009
Bk   Num    Ans                           Question                              Answer A                  Answer B           Answer C                Answer D             Illustr
                  Which of the devices listed is indicated by the          Thyristor                  Diode               Capacitor              Transistor
12   1722   B     electronic symbol lettered as "A", shown in the                                                                                                        EL-0016
                  illustration?
                  One method of testing for a reversed shunt field coil in iron bar across            magnetic compass test lamp across          copper jumper
                  a DC motor is by connecting the coil to a low voltage    each field                 placed near each adjacent fields           across the
12   1723   B
                  source, and test for polarity using a/an __________.                                field                                      interpole
                                                                                                                                                 connections
                  Which of the listed motors will operate at the highest      A four-pole             A four-pole        A six-pole              A six-pole
                  RPM, assuming that each operates at the same                synchronous             induction motor    synchronous             induction motor
12   1724   A
                  frequency?                                                  motor under             under no load.     motor under             under full load.
                                                                              normal load.                               normal load.
                  Which of the following statements represents the            Be certain that the     Never alter the    Replacement of a        The replacement
                  important factor that must be considered when               replacement diode       diode alignment to diode also              diode must be
                  replacing a faulty diode in a generators excitation field   is installed with the   cause a change in requires balancing       dipped in varnish
                  rectifier assembly?                                         same polarity as        the neutral plane. of the rotor with a     prior to installation
                                                                              the one removed.                           one-piece rotor         to protect against
12   1725   A                                                                                                            lamination to be        humidity.
                                                                                                                         shrunk fit and
                                                                                                                         keyed to the shaft.



                  When charging a wet cell nickel-cadmium battery,            the charging rate extended trickle          the specific gravity   add distilled water
                  __________.                                                 should never allow charging should          of the electrolyte     just prior to
                                                                              gassing            be avoided               will be generally      charging to insure
12   1726   C                                                                                                             unaffected by the      proper mixing
                                                                                                                          state of charge



                  A bus disconnect link is used to isolate __________.        one bus bar from        the generator       different bus          positive and
                                                                              the ground              circuit breaker     phases from the        negative buses
12   1727   B
                                                                              detection system        from the bus        equalizer              from the neutral
                                                                                                                          connection
                  Two DC drive propulsion motors provide input to a       a tripped reverse           a tripped reverse   overheating of the     a tripped variable
                  single output reduction gear. Upon relieving the watch, power relay                 current relay       load inverter          frequency
                  you notice that the starboard motor indicators show                                                                            converter
12   1728   B     reduced voltage and zero current compared to normal
                  voltage and current indicated on the port mot

                  Voltage failure of an AC generator may be caused by         an open in the          a tripped bus      high mica               short circuit in the
12   1729   A     __________.                                                 rotor field circuit     circuit breaker    segments on the         stator coils
                                                                                                                         stator bus bar
                  Electrical power loss due to hysteresis is a result of      arcing at the           pulsating terminal heat generated by       excessive field
12   1730   C     __________.                                                 brushes                 current            magnetic polarity       current
                                                                                                                         reversals
                                                                                137                                                       Electrical Questions-April 2009
Bk   Num    Ans                           Question                                  Answer A              Answer B              Answer C               Answer D           Illustr
                  A three-phase alternator is operating at 450 volts, 250       38.97 kw              116.91 kw             155.88 kw              194.85 kw
                  amps at 0.6 power factor. If the power factor increases
12   1731   A
                  to 0.8, the kw load potential will increase by
                  __________.
                  The best tool to use to remove a ball bearing from the        rawhide hammer        brass mallet          wheel puller           wooden mallet
12   1732   C
                  shaft of a motor would be a __________.
                  On large generators, space heaters are used to                keep the machine      maintain rotor and prevent                   prevent
                  __________.                                                   at ambient            stator winding     condensation in           electrolysis due to
                                                                                temperature of the    temperatures       the lube oil              condensation in
                                                                                machinery space       above the dew                                the bearings
12   1733   B                                                                                         point to prevent
                                                                                                      the formation of
                                                                                                      condensation

                  If a small electric motor has been immersed in salt           I only                II only               both I and II          neither I or II
                  water, it should be __________.

12   1734   A     I. thoroughly rinsed in fresh water and completely
                  dried
                  II. initially started with reduced voltage
                  If a DC motor runs faster than designed, with all other       open shunt field      open armature coil reversed         overload
12   1735   A     conditions being normal, the possible cause could be          coil                                     commutating pole
                  a/an __________.
                  Wet armature windings in a D.C. motor may lead to             reduced voltage       reduced current   increased                  overheating
12   1736   D
                  __________.                                                                                           resistance
                  As shown in the illustration, what is the purpose of the      Ensures the motor Ensures the motor Allows the motor               Allows the motor
                  Time Delay (TD) coil in the circuit?                          cannot be started cannot be started to come up to                  to come up to
                                                                                until the overload until the            speed before               speed before
12   1737   D                                                                   relays are reset.  accelerating coil is placing the starting       bypassing the         EL-0104
                                                                                                   energized.           resistors in the           starting resistors.
                                                                                                                        circuit.
                  A low voltage source is applied to the collector rings of     high voltage          low or zero voltage   fluctuating            steady voltmeter
                  a salient-pole alternator to test for shorted coils. As the   reading, while the    reading, while the    voltmeter reading,     reading, while the
                  voltage drop across each coil is recorded, a coil with a      other coil readings   other coils will      while the other coil   other coil readings
12   1738   B     short circuit will be indicated by a __________.              will have an equal    have higher           readings are           are fluctuating
                                                                                or lower value        readings              steady




                                                                                  138                                                       Electrical Questions-April 2009
Bk   Num    Ans                         Question                                Answer A             Answer B           Answer C              Answer D         Illustr
                  The purpose of the commutator and brushes on a DC        transfer generated   convert the peak provide a sliding        reduce sparking
                  generator is to __________.                              direct current       alternating voltage contact method to     between the
                                                                           voltage from the     generated within excite the field         armature and the
                                                                           armature to the      the armature to a                         carbon brushes
12   1739   B                                                              line                 direct current
                                                                                                voltage to the line



                  Which of the following statements concerning a wet       When mixing the      When mixing the      Nickel-Cadmium       The electrolyte of
                  cell Nickel-Cadmium battery is true?                     electrolyte always   electrolyte always   batteries should     an idle Nickel-
                                                                           add acid to the      add water to the     be charged with a    Cadmium battery
                                                                           water.               acid.                voltage of           must be replaced
12   1740   C                                                                                                        approximately 1.85   monthly to
                                                                                                                     volts per cell       maintain battery
                                                                                                                                          condition.

                  Hand-portable phase sequence indicators should be        installing a new  preparing to make replacing a        all of the above
                  used when __________.                                    power factor      the ships shore   defective solenoid
12   1741   B
                                                                           switchboard meter power connection

                  The specific gravity of the electrolyte solution in a lead is not affected    remains the same would read               provides an
                  acid battery __________.                                   during charging    during discharge approximately            indication to the
12   1742   D
                                                                                                                 1.830 when               state of charge of
                                                                                                                 discharged               the battery
                  Which of the following materials is recommended for      grade 00             canvas wiper     crocus cloth             smooth file
12   1743   C     finishing the slip rings of an electric motor after      sandpaper
                  grinding or turning?
                  AC and DC generators are similar in that they           both initially        both rectify the     both operate at 60 both supply three-
                  __________.                                             generate              voltage before       cycles             phase power
12   1744   A
                                                                          alternating           delivery
                                                                          voltages
                  A useful instrument for checking the performance of an hand or battery-       vibrating-reed       hook-on voltmeter- D'Arsonval iron-
12   1745   C     operating poly phase AC motor would be a                operated megger       frequency meter      ammeter            vane probe
                  __________.
                  The operating torque of the disk or timer element in an the main bus          a separate battery line voltage           electromagnets
12   1746   D     AC reverse power relay is obtained from __________.                           source

                  AC generator circuits are protected against              main bus             a separate battery reverse current        reverse power
12   1747   D     malfunctions due to prime mover power loss by the        disconnect links     backup             relays                 relays
                  use of __________.
                  DC generator circuits are protected against              main bus             a separate battery reverse current        reverse power
12   1748   C     malfunctions due to prime mover power loss by the        disconnect links     backup             relays                 relays
                  use of __________.

                                                                              139                                                    Electrical Questions-April 2009
Bk   Num    Ans                          Question                                 Answer A               Answer B        Answer C             Answer D                Illustr
                  From the information given in the illustration, which of   Automation should     A interlock       The emergency       All of the above
                  the following statements is correct?                       automatically start   prevents circuit  generator output is
                                                                             the emergency         breaker 52N from rated at 400 amps.
                                                                             generator and         being closed when
                                                                             close circuit         the emergency
12   1749   D                                                                breaker 52E if        generator is on                                                   EL-0106
                                                                             circuit breaker 52N   line.
                                                                             is manually tripped
                                                                             open.



                  A change in field excitation of an alternator operating in alternator            phase sequence        reactive power         active power
12   1750   C     parallel will cause a change in its __________.            frequency

                  A milliammeter, with a full scale deflection reading of 4.9 and 5.1              4.8 and 5.2           4.5 and 5.5            4.0 and 6.0
                  100 milliamps, is known to have an accuracy of plus or milliamperes              milliamperes          milliamperes           milliamperes
12   1751   A     minus 2%. A meter reading of 5 milliamps would
                  indicate a line current of between ________.

                  What would be the terminal voltage and amp-hour            24 volts and 75       24 volts and 150      24 volts and 225       36 volts and 450
12   1752   C     capacity at terminals A and B if each battery was rated    amp-hours             amp-hours             amp-hours              amp-hours            EL-0107
                  at 75 amp-hours and 12 volts?
                  A megger is being used to test the insulation of an AC     continue to rise as   remain constant       continue to drop       stabilize after
                  generator. The resistance value of a dry, clean            test potential is     as the temperature    as test potential is   approximately 2-4
                  winding will __________.                                   maintained,           of the windings       maintained,            minutes of
                                                                             becoming fairly       increases             becoming fairly        fluctuation
12   1753   A                                                                steady as the                               steady after 5-7
                                                                             dielectric-                                 minutes
                                                                             absorption effect
                                                                             of insulation
                                                                             stabilizes
                  Which statement is true concerning a split-phase       Motor rotation can        Motor speed can       The motor will run     Motor rotation can
                  induction motor?                                       be reversed               be readily adjusted   as a generator         be reversed by
12   1754   D                                                            without changing          from zero to full     with the proper        reversing the
                                                                         the windings or           speed.                wiring.                leads on the
                                                                         leads.                                                                 starting winding.
                  Which of the following statements is true concerning a The motor is              Resistance is      The starting              The field winding
                  large polyphase synchronous main propulsion motor? started as an                 gradually added to current is held           is energized for
12   1755   A
                                                                         induction motor.          the rotor circuit. below the rated           starting purposes
                                                                                                                      current.                  only.



                                                                               140                                                        Electrical Questions-April 2009
Bk   Num    Ans                          Question                             Answer A                     Answer B             Answer C               Answer D         Illustr
                  Which of the following represents the accepted method Carefully using a             Blowing a high        Using a vacuum        Using carbon
                  of cleaning dust and foreign particles from electrical soft copper bristle          velocity stream of    cleaner to remove     tetrachloride as a
                  equipment while limiting damage to electric            brush.                       compressed air        debris from the       cleaning solvent to
12   1756   C     components?                                                                         rapidly across the    components.           clean the
                                                                                                      components.                                 components.

                  A load with an impedance of 440 ohms is connected            2.5 amps               25 amps               250 amps              current cannot be
                  across the secondary of a step-up transformer. If the                                                                           determined with
12   1757   B     input voltage is 110 VAC and the step-up ratio is 10,                                                                           information given
                  what will be the primary current?

                  Germanium semiconductor diodes are commonly used potentiometers                     rectifiers            power sources         photocells
12   1758   B
                  as __________.
                  The amount of voltage induced in the stator windings the number of field            the number of slip the strength of the all of the above
                  of a modern AC generator depends mainly on           poles energized                rings connected to magnetic field
12   1760   C
                  __________.                                                                         the commutator

                  Routine A.C. motor maintenance should include                temperature            inspection of the    verifying RPM if a     rotor balance
                  periodic __________.                                         readings at normal     motor's internals    synchronous            check
                                                                               loads to detect        for loose rotor bars motor
12   1761   A                                                                  abnormal               or field poles
                                                                               temperature rises

                  Materials that retain a large part of their magnetization,   low hysteresis loss high flux density        high permanence       high ductility
12   1762   C     after the magnetizing force is removed, are said to
                  have __________.
                  Which of the listed colors properly describes a DC           Shiny blue             Burnished green       Brick red             Chocolate brown
12   1764   D     motor commutator when correct commutation is taking
                  place?
                  When checking the specific gravity of battery                The battery is fully   Any water that has    The hydrometer        Temperature has
                  electrolyte with a hydrometer, which of the following        charged when the       been previously       reading will be       no effect on
                  statements is true?                                          indicator floats       added to the cells    inaccurate if taken   hydrometer
12   1765   C                                                                  deep and low in        will increase the     immediately after     readings.
                                                                               the electrolyte.       specific gravity of   water is added to
                                                                                                      the solution.         the cell.

                  The air gap provided in an induction motor should be         any decrease in   an increase in             increase in           any increase in
                  checked periodically with a feeler gage to detect            motor magnetizing hysteresis loss            apparent power        rotor bearing wear
12   1766   D
                  __________.                                                  current                                      factor

                  A common method used to control the speed of a               varying the input      increasing the        decreasing the        increasing the
                  synchronous AC propulsion motor on a diesel-electric         frequency of the       motor voltage         motor voltage         current to the
12   1767   A
                  propulsion drive is by __________.                           voltage to the                                                     motor
                                                                               motor
                                                                                 141                                                         Electrical Questions-April 2009
Bk   Num    Ans                           Question                              Answer A             Answer B              Answer C               Answer D         Illustr
                  Some electrical schematics use "binary values" (Base      0110                 1110                  0111                   1001
                  2), to represent and identify automation alarm
12   1768   C     addresses. Which of the following represents the
                  "binary value" for the decimal number 7 (Base 10)?

                  To best determine the state of charge of a wet cell       measure the          measure the           test the electrolyte use a ohm meter
12   1770   B     nickel-cadmium battery, you should __________.            output amperage      voltage while         specific gravity     on the highest
                                                                                                 under a load                               scale
                  An AC generator produces 60 Hz at 1800 RPM. If the remain at 60 Hz             increase to 61 Hz     decrease to 59 Hz increase to 63 Hz
12   1771   B     generator speed is increased to 1830 RPM, the cycles
                  will __________.
                  If a DC motor runs hot, the cause may be __________. undercut mica             low ambient       clogged ventilation an open in the
12   1772   C
                                                                         condition               temperature       ducts               series field
                  Brushes in a generator must be positioned in the       yoke                    armature windings field pole windings commutator
12   1773   D     neutral plane to avoid sparking between the brushes
                  and the __________.
                  If the connections for the field and the armature on a the motor will run      the motor will not    the direction of       the direction of
12   1774   C     DC motor are reversed, __________.                     as a generator          run                   rotation will be the   rotation will be
                                                                                                                       same                   reversed
                  The most practical method used for resurfacing a          turn it down in the use a portable         use a hand stone       burnish it with
                  ship's main propulsion motor commutator is to             ship's lathe        grinding and metal                            commutator
12   1775   B     __________.                                                                   cutting rig                                   stones
                                                                                                attached to the
                                                                                                motor frame
                  According to 46 CFR Subchapter J, electric motors         40°C                50°C               60°C                       70°C
                  operating in a boiler room machinery space must be
12   1776   B
                  designed for an ambient temperature of __________.

                  When a nickel-cadmium battery begins gassing while        do nothing as this   add distilled water   add potassium       increase the
                  connected to the battery charging circuit, you should     is a normal          to each cell to       hydroxide to each charging rate
                  __________.                                               condition when       increase the          cell to reduce the
12   1777   A                                                               charging             specific gravity of   specific gravity of
                                                                                                 the electrolyte       the electrolyte

                  What would be the terminal voltage and amp-hour           6 volts and 50       12 volts and 150      24 volts and 200       36 volts and 300
12   1778   B     capacity at terminals A and B if each battery was rated   amp-hours            amp-hours             amp-hours              amp-hours           EL-0107
                  at 50 amp-hours and 6 volts?
                  What would be the terminal voltage and amp-hour           12 volts and 50      12 volts and 150      24 volts and 50        24 volts and 150
12   1779   D     capacity at terminals A and B if each battery was rated   amp-hours            amp-hours             amp-hours              amp-hours           EL-0107
                  at 50 amp-hours and 12 volts?
                  What would be the terminal voltage and amp-hour           12 volts and 600     12 volts and 1200 36 volts and 600           36 volts and 1200
12   1780   A     capacity at terminals A and B if each battery was rated   amp-hours            amp-hours         amp-hours                  amp-hours           EL-0107
                  at 200 amp-hours and 6 volts?

                                                                              142                                                        Electrical Questions-April 2009
Bk   Num    Ans                            Question                             Answer A              Answer B               Answer C               Answer D       Illustr
                  A lead-acid battery can deliver 20 amperes               20                    40                    200                    400
12   1781   C     continuously for 10 hours with an ampere-hour rating
                  of __________.
                  In a diesel electric plant, raising the AC generator's   increase in speed decrease in speed operate with a         operate with a
12   1782   A     field excitation will cause the DC propulsion motor to                                         lower power factor higher power
                  __________.                                                                                                         factor
                  An advantage of DC motors over AC motors is that         are less expensive require less       offer infinite speed all of the above
12   1784   C
                  they __________.                                                            maintenance        variation
                  A DC ammeter would normally be connected                 in series with a   in parallel with a with internal        without regard to
12   1785   A
                  __________.                                              circuit            circuit            shunts only          polarity
                  A megohmmeter is used to measure __________.             voltage            insulation         capacitance          power
12   1786   B                                                                                 resistance values

                  Power conversion for use in AC propulsion drive          cyclo-converters    pulse width             load commutated        All of the above
12   1787   D     motors can be accomplished by __________.                                    modulated               inverters
                                                                                               inverters
                  Which of the following is a disadvantage of electric     The propeller       Propulsion motors       Location of electric   Main propulsion
                  drive propulsion systems?                                speed and           are required along      power generation       power may also be
                                                                           direction of        with electrical         machinery is           directed to ships
12   1789   B                                                              rotation are easily power generation        flexible.              electrical service
                                                                           controllable.       machinery.                                     distribution.



                  Which statement is NOT true concerning electric          The propeller         Lower                 Flexibility of         Ability to be
                  propulsion drives?                                       speed and             transmission          arrangement            utilized as a
                                                                           direction of          losses compared       between the prime      source of ships
12   1790   B                                                              rotation are easily   to other types of     mover and motor.       service power.
                                                                           controllable.         propulsion drives.



                  A twelve volt lead-acid battery is constructed of        one cell              three cells           six cells              twelve cells
12   1791   C
                  __________.
                  A cyclo-converter (CCV) is a static power converter      provides              converts ac power     converts dc power      provides constant
                  that __________.                                         adjustable            to dc power in a dc   to ac power in an      frequency output
                                                                           frequency to          propulsion drive      ac propulsion          power to an ac
12   1792   A                                                              power an ac           system                motor                  propulsion drive
                                                                           propulsion drive                                                   motor
                                                                           motor




                                                                             143                                                        Electrical Questions-April 2009
Bk   Num    Ans                         Question                              Answer A             Answer B             Answer C                Answer D         Illustr
                  Moisture accumulating in electric motors and generator feeding current       short circuiting the short circuiting the   obtaining current
                  windings having a cold insulation resistance greater   into the windings     armature and field field windings and       from a DC source
                  than 50,000 ohms may be baked out with internal heat. at low voltage         windings             passing current        such as an electric
                  This heat can be developed by __________.                                                         through the            welder and
                                                                                                                    armature               feeding it into the
12   1793   A                                                                                                                              armature while
                                                                                                                                           running the motor
                                                                                                                                           at full speed



                  A series wound DC motor has its armature and field       the proper          the proper         a reversing        dynamic braking
                  connected in series with a resistor. When the motor is   connections for     connections for an controller circuit
12   1794   D
                  disconnected from its power supply, this motor will      across the line     automatic strip
                  exemplify __________.                                    starting            heater
                  An electric propulsion drive system in which the         integrated system   dedicated system composite system multi-purpose
                  propulsion generator supplies power to both the                                                                    system
12   1796   A
                  propulsion motor and ship service loads is referred to
                  as a __________.
                  Equipment for dc propulsion drive systems usually        generators which an induction type       a synchronous          generators which
                  includes ________.                                       produce dc power propulsion motor        type propulsion        produce ac power
                                                                           that is converted                        motor                  that is converted
12   1797   D                                                              to ac power for the                                             to dc for the
                                                                           propulsion motor                                                propulsion motor



                  The type of motor generally used in DC propulsion        series wound        squirrel cage        shunt wound            differential-
12   1798   C
                  drive systems is the __________.                                             induction                                   compound
                  Speed control of a DC propulsion motor is             adjusting the          the use of a load-   the use of static      adjusting the input
                  accomplished by __________.                           output frequency       commutated           power converters       voltage to the
12   1799   D
                                                                        of the electric        inverter                                    motor
                                                                        power source
                  Reversal of a DC propulsion motor is achieved through reversing the        the use of a shunt     reversing the          the use of a 12
                  __________.                                           direction of current field regulator        phase sequence         pulse converter
12   1800   A                                                           flow in the motor                           of the incoming
                                                                        field windings                              voltage

                  An electric heating element supplied with 120 volts      15 watts            45.57 watts          8 watts                1800 watts
12   1801   D     draws 15 amps. How much power will be consumed?




                                                                            144                                                       Electrical Questions-April 2009
Bk   Num    Ans                                Question                                  Answer A              Answer B                Answer C             Answer D           Illustr
                  As shown in the illustration of a vessels navigational            The new lower          Solenoid 'H' will      The alarm horn at    There may be
                  lighting circuit, if light 'E1' burns out, a failure alarm will   wattage light at       overheat.              'G' may not have     insufficient current
                  normally be energized at 'G'. If 'E1' is replaced with a          'E1' will                                     sufficient voltage   to open contactor
12   1802   D     light of a smaller wattage, which of the following is             immediately burn                              to provide sound.    'H2' to silence the    EL-0058
                  true?                                                             out.                                                               alarm.

                  Uneven wear of the commutator surface on a direct                 rapid change in        excessive          incorrect brush          unequal pole
12   1803   C     current propulsion motor can be caused by                         load                   operation at light staggering               spacing
                  __________.                                                                              load
                  Which of the listed conditions is an advantage of a PN            Smaller size.          No warm up time. More reliable.             All of the above.
12   1805   D
                  diode over a vacuum diode?
                  What would be the voltage measured across the load                225 volts              292 volts              360 volts            450 volts
12   1807   C                                                                                                                                                                 EL-0083
                  as shown in the illustration.
                  One function of the movable contacts in a drum-type               regulate the           maintain               insulate the         limit the amount of
                  motor controller is to __________.                                current to the         resistance             operating handle     load put on the
12   1808   A
                                                                                    motor                  contacts in clean                           motor
                                                                                                           condition
                  The plates of a wet cell NiCad storage battery are                potassium              cadmium sulfate        silver oxide and      nickel hydroxide
12   1809   D     made from __________.                                             hydroxide and          and lead peroxide      cadmium sulfate       and cadmium
                                                                                    nickel sulfate                                                      hydroxide
                  The propeller shaft speed in a diesel-electric, AC-               generator speed        number of motor        field strength of     output frequency
12   1810   D     synchronous, propulsion drive motor is changed by                                        poles                  the generator         of the power
                  varying the __________.                                                                                                               converter
                  While standing watch onboard a diesel-electric                    check the            notify the bridge        send the oiler to     reduce load by
                  propulsion drive ship, you notice the main transformer            transformer          that you need to         look for fires in the tripping lighting
12   1811   A     core temperature slowly rising. You should first                  ventilation fans for slow down                transformer           circuits
                  __________.                                                       proper operation

                  The torque produced by a DC motor armature is the                 work done by the       effective armature maximum moment perpendicular
                  product of the force acting at the armature surface               armature in one        diameter at which arm at the center distance to its
12   1814   D     multiplied by __________.                                         revolution             the force acts     of rotation of the center of rotation
                                                                                                                              armature

                  The rotation of the main propulsion motor in a modern             changing the           reversing the          electronically       power directional
                  AC propulsion drive system is reversed by                         direction of current   direction of current   changing the         relays
                  __________.                                                       flow in the motor's    flow in the            phase sequence
12   1815   C                                                                       field winding          armature               of the voltages
                                                                                                                                  generated by the
                                                                                                                                  power converter
                  The propulsion motor most often utilized in an ac drive squirrel cage                    synchronous type wound rotor                split phase
12   1816   B     system operating in the moderate to high power range induction type                      with wound field induction type             induction type
                  is the ________.

                                                                                      145                                                         Electrical Questions-April 2009
Bk   Num    Ans                         Question                                Answer A           Answer B              Answer C            Answer D            Illustr
                  The Azipod propulsion system is a ________.               electric drive     electric drive       electric drive       electric drive
                                                                            system using       system that          system where the     system in which
                                                                            water jets         incorporates a DC    propulsion motor     the motor drives a
                                                                                               motor                is installed in a    controllable pitch
12   1817   C                                                                                                       submerged            propeller (CPP)
                                                                                                                    housing capable of
                                                                                                                    swiveling

                  Which of the following statement is FALSE concerning The pod assembly The system allows The system                     The system
                  Azipod propulsion systems?                            swivels on a      full turns at high eliminates the              requires the use of
12   1818   D
                                                                        vertical axis.    speed.             need for a                  a controllable pitch
                                                                                                             separate rudder.            propeller.
                  An electric propulsion drive system in which the      integrated system dedicated system composite system              multi-purpose
12   1819   B     propulsion generator only supplies power to the                                                                        system
                  propulsion motor is referred to as a __________.
                  If the approximate voltage to be measured in an       use the lowest    connect the meter only have to                 use the highest
                  electric circuit is not known, you should __________. voltage range on in series with the calibrate the meter          voltage range on
12   1820   D
                                                                        the voltmeter     circuit            before using it             the voltmeter

                  Which of the following statements is true if a 100 watt   The 75 watt lamp The 100 watt lamp Current flow will be The 75 watt lamp
                  lamp and a 75 watt lamp are connected in parallel         will draw as much will have a greater the same across will have a higher
12   1821   D     across a 100 volt power supply?                           current as the 100 resistance.        each lamp.        resistance.
                                                                            watt lamp.

                  When you are making a high potential test (megger)        good insulation    bad insulation       high insulation      a high slot
                  on the motor coils of repaired electrical machinery, a                                            power factor         discharge factor
12   1822   B
                  rise in leakage current indicates __________.

                  To perform an insulation resistance test of an         both ends of the      the input line lead one end of the coil armature brush
                  individual electric motor coil, the megohmmeter should coil                  and one end of the and the frame of     pigtail and the
12   1823   C
                  be connected to __________.                                                  coil                the machine         input line lead

                  As shown in the illustration, the electrical symbol is    Shunt motor.       Series motor.        Compound motor. Tri-field motor.
12   1824   C     used to indicate which of the listed types of motors?                                                                                         EL-0054

                  Which of the following statements concerning the          The electrolyte    The specific         The most accurate    The temperature
                  specific gravity of a battery electrolyte is true?        becomes less       gravity reading is   hydrometer           does not affect the
                                                                            dense when it is   lowered when the     reading is           specific gravity of
                                                                            cooled.            electrolyte          obtained             the electrolyte.
12   1825   B                                                                                  temperature has      immediately after
                                                                                               increased.           water is added.



                                                                              146                                                     Electrical Questions-April 2009
Bk   Num    Ans                         Question                                Answer A            Answer B           Answer C           Answer D               Illustr
                  An AC generator is prevented from becoming                overspeed trip     reverse power       back pressure trip governor controls
12   1826   B
                  motorized by the use of a/an __________.                                     relay
                  To determine the state of charge of a wet cell nickel-  check the            use the constant    check no load          check voltage
12   1827   D     cadmium battery, you should __________.                 electrolyte with a   specific gravity    voltage                under nominal
                                                                          hydrometer           method                                     load
                  An ohmmeter reading of 'zero' ohms between the ends continuity               a partial ground    open circuit           a short circuit
12   1828   A     of a wire conductor would provide a positive indication
                  of __________.
                  When replacing a fuse with one of a higher rating than It endangers the      It reduces the       It increases the      It creates a larger
                  the original, which of the following is true?           apparatus it is      possibility of short efficiency of the     voltage drop in the
                                                                          supposed to          circuits.            equipment by          circuit being
12   1829   A                                                             protect.                                  allowing more         protected.
                                                                                                                    current to be used.

                  During maintenance of circuit breakers, __________.       always smooth        never pass more inspect for wear always apply a thin
                                                                            roughened contact than rated breaker and misalignment film of oil on
                                                                            surfaces with a file current through of main contacts contact surfaces
12   1830   C                                                                                    the overload
                                                                                                 heater element

                  Two 100 watt light bulbs are connected in parallel        200 watts          100 watts           50 watts            equal to the
                  across a 100 volt power supply. The total power                                                                      product of the
12   1831   A     developed in the circuit is __________.                                                                              amperes times the
                                                                                                                                       voltage in each
                                                                                                                                       branch
                  According to 46 CFR Part 58, if a steering motor          overload condition overload condition motor running        standby steering
                  becomes overloaded, the __________.                       of 5% will trip the will be indicated indicator will begin pump will start
                                                                            motor off the line audibly and        to flash 'on' and    automatically and
                                                                            immediately         visually at the   'off' in response to come on the line
12   1832   B                                                                                   main machinery- the sustained
                                                                                                control station.  overload condition



                  In order to safely carry out repairs to a generator circuit reverse power    bus disconnect      generator bus fuse power directional
                  breaker, it must be isolated from the bus. This is          relay            link                connections        relay
12   1833   B
                  accomplished by opening the __________.

                  Which of the listed electrical devices is represented by Fixed resistance    Coil with magnetic DC motor or             Transformer
12   1834   D     the symbol shown in the illustration?                    resistor            core               generator shunt                               EL-0055
                                                                                                                  field


                                                                              147                                                  Electrical Questions-April 2009
Bk   Num    Ans                             Question                             Answer A                Answer B              Answer C             Answer D           Illustr
                  On an engine throttle control system, the auxiliary        overlap sensors       limit switches         differential relays   analog relays
                  control circuits are provided with devices to prevent
12   1835   B     excessive over travel of the actuating valve by the
                  control motor. These devices are commonly called
                  __________.
                  If you obtain a low resistance reading with an             continuity in the   continuity in the   an open circuit            an open circuit in
                  ohmmeter connected between terminals "A" and "C"           circuit between "A" circuit between "C" between "A" and            both windings
12   1836   A                                                                                                                                                         EL-0074
                  of the three-phase, wye-connected winding shown in         and "C"             and "B"             "C"
                  the illustration, there is __________.
                  "Low Voltage Release" (LVR) protection used in some        The controller will   The controller will    The controller        The controller will
                  shipboard motor starters and other control equipment       trip the circuit      require manual         uses a phase          allow a motor to
                  will have which of the following characteristics?          contactors when       resetting upon         sensitive relay to    automatically
12   1837   D                                                                motor over-speed      restoration of         trip contacts in      restart upon
                                                                             occurs.               normal voltage.        series with the       restoration of
                                                                                                                          holding coil of the   normal voltage.
                                                                                                                          starter.
                  Increasing the load on the secondary windings of a         decrease in the       increase in the        decrease in the       increase in the
12   1838   D
                  transformer will cause a/an __________.                    primary voltage       primary voltage        primary current       primary current
                  As shown in the illustration, which listed action will     Contacts 'H-1', 'H-   The motor will start   The "A-1" and "A-     Only the "H2"
12   1839   A     occur when push button "R" is depressed?                   2' and 'H-3' close.   to run in reverse.     2" contacts open.     contact will close.   EL-0017

                  The timer element of a reverse power relay will activate the power flow is       the power flow is the movement of            the load difference
                  when __________.                                         the same as the         the opposite to the the disk is damped       between
                                                                           tripping direction      tripping direction by a permanent            generators is more
12   1840   A                                                                                                          magnet                   than 10 percent.



                  If the voltage supplied to the lighting circuit is 110 volts, 0.08 amps          0.91 amps              1.10 amps             90.9 amps
12   1841   B     how much current is used by a 100 watt light bulb?

                  An AC generator power panel is fitted with two             the incoming          the generators are the generators are the generator
                  synchronizing lamps and a synchroscope. When               generator voltage     out of phase and in phase but one breaker may be
                  paralleling, if the synchroscope pointer is at the noon    is too low            one lamp is        lamp is burned out closed
12   1842   B     position and one synchronizing light is bright while the                         burned out
                  other remains dark, this indicates that __________.

                  Which of the listed faults can only be eliminated by       Sparking brushes      Eccentricity           High mica             Incorrect brush
12   1843   B     turning or grinding the face of a commutator with a                                                                           angle
                  rigidly supported tool?



                                                                               148                                                         Electrical Questions-April 2009
Bk   Num    Ans                            Question                                Answer A              Answer B            Answer C               Answer D           Illustr
                  The torque and current curves for a three-phase             As slip increases,    The pullout point   At stand still,       If the motor is
                  induction motor with a cage rotor, are shown in the         rotor reactance       on the torque       stator current is     loaded to the point
                  illustration. Which of the following statements is true     decreases.            curve is about      150% of normal.       where 40% slip
12   1844   D     concerning the depicted curves?                                                   seven times the                           has resulted, it will   EL-0056
                                                                                                    normal full load                          stall.
                                                                                                    torque value.
                  While underway onboard a DC diesel electric drive           notify the bridge     decrease the      decrease the main decrease the
                  ship, you notice excessive sparking of the brushes on       that you will need    speed of the main generator voltage motor field current
12   1845   A
                  the main propulsion motor. You should first                 to slow down          generator
                  __________.
                  Which of the listed conditions could cause a recently       Reversed interpole Low series field       High shunt field      Excessive
12   1846   A     overhauled DC motor to have excessively hot windings        polarity           current                current               humidity
                  and sparking at the brushes?
                  Two DC drive propulsion motors provide input to a           a tripped reverse     a tripped reverse   overheating of the a tripped variable
                  single output reduction gear. Upon relieving the watch,     power relay           current relay       load inverter      frequency
                  you notice that the starboard motor indicators show                                                                      converter
12   1847   B     zero current compared to normal voltage and current
                  indicated on the port motor. The problem with the
                  starboard motor could be __________.

                  A three-phase electrical system is equipped with            the dark lamp      there is a ground there are grounds the voltage to the
                  ground detecting lamps. If one of the lamps is dark,        must be replaced   in the line with the in two of the three dark lamp is less
12   1848   A
                  and remains dark when the test switch is operated, this                        dark lamp            phases              than that of the
                  indicates __________.                                                                                                   system
                  If coil 'R1-R2' on the transmitter shown in figure "A" of   make coils 'S1-S2- ring at the          receive a higher    align itself to the
                  the illustration is turned 30 degrees clockwise, the        S3' turn faster    receiving station    voltage depending same position if
12   1850   D     corresponding coil 'R1-R2' on the receiver will             because of         until the turning    on the turns ratio free to move                 EL-0092
                  __________.                                                 induced currents stops

                  Three 12 volt, lead-acid, batteries connected in series     12 volts              24 volts            36 volts              48 volts
12   1851   C
                  will develop __________.
                  The existing resistance of a conductor is dependent         inductive             material and       capacitive             material and
12   1852   D     upon its length, cross-sectional area, __________.          reactance and         insulation         reactance and          temperature
                                                                              insulation                               material
                  Which of the following statements describes what will       The primary           The stator current The slip will          The slip value,
                  occur if the motor shown in the illustration is required    counter emf will be   will increase.     decrease.              stator current
12   1854   B     to carry 150% of full load?                                 increased.                                                      curve, and torque       EL-0056
                                                                                                                                              curve will all
                                                                                                                                              coincide.
                  Which of the following statements concerning AC             The power factor      True power in an    Inductive             The current lags
                  circuits is correct?                                        of a resistive        inductive circuit   reactance varies      the voltage in a
12   1855   C                                                                 circuit is always     always equals       directly with the     capacitive circuit.
                                                                              zero.                 apparent power.     source frequency.

                                                                                149                                                        Electrical Questions-April 2009
Bk   Num    Ans                           Question                                  Answer A         Answer B               Answer C              Answer D         Illustr
                  How will a molded-case circuit breaker react after it       The breaker will   The breaker           The breaker           The thermal
                  has tripped, as a result of an overloaded circuit?          trip again if      handle will lock in   handle will lock in   element must be
                                                                              immediately reset. the OFF position.     the tripped           replaced after an
                                                                                                                       position until the    overload trip has
12   1856   A                                                                                                          thermal element       occurred before it
                                                                                                                       cools down.           can be restored
                                                                                                                                             into service.

                  Prior to performing any internal maintenance on a           de-energize and     tag and lock out     engage shaft          All of the above
                  large DC main propulsion motor, precautions should          lock out thermal    the motors main      brake to prevent
                  be taken to __________.                                     heater circuits and circuit breaker      the rotor from
                                                                              any other auxiliary                      accidentally
12   1857   D                                                                 circuits located                         turning
                                                                              inside the motor
                                                                              housing

                  Heat sinks are most frequently used with __________. power transistors          vacuum tubes         LED's                 LCD's
12   1860   A
                  What is the wattage of a heating element drawing a          30 watts            99.97 watts          360 watts             3600 watts
12   1861   D
                  current of 30 amperes, at 120 volts?
                  On a digital numerical display readout, what would be       6                   7                    8                     9
                  the minimum number of LED segments required to
12   1862   B
                  form and display any digit 0 through 9?

                  The windings of electric generators during short idle       allowed to cool     flashed with direct kept warm by           relieved of all
                  periods should be __________.                               slowly to ambient   current to remove using strip or           capacitive charge
12   1863   C                                                                 temperatures        any residual        space heaters          by grounding the
                                                                                                  magnetism                                  conductors

                  Which of the diagrams shown in the illustration depicts     A                   B                    C                     D
12   1864   B     the proper method of aligning brushes on a                                                                                                      EL-0057
                  commutator?
                  What controls rudder movement when the Operation            Steering wheel      Non-follow-up        Gyro-compass          Course selector
12   1865   B     Selector Switch shown in the illustration is in the 'NFU'                       control lever                              pointer              EL-0097
                  position?
                  A basic electrical meter sensing device that responds       D'Arsonval meter    Bourdon meter        Vibrating Reed        Transducer meter
                  to the flow of current through an electromagnetic coil      movement            movement             movement              movement
12   1866   A     commonly used in DC ammeters, voltmeters, and ohm
                  meters is called a __________.

                  The leads from a ohmmeter are attached to the leads         open field coil     shorted field coil   grounded field coil shunted field coil
12   1867   A     of an AC motor field coil. A reading of infinity is
                  obtained indicating a/an __________.

                                                                                  150                                                   Electrical Questions-April 2009
Bk   Num    Ans                              Question                               Answer A              Answer B              Answer C             Answer D        Illustr
                  In the illustration, if both generators were operating in    Increase the          Increase the          Increase the         Increase the
                  parallel and the Watt meter of panel 3 indicated a           governor setting in   governor setting in   setting of the       setting of the
                  significantly higher value than the Watt meter on panel      panel 1 and           panel 3 and           voltage regulator    voltage regulator
                  1, which of the following procedures should you follow       decrease the          decrease the          in panel 3 and       in panel 3 and
12   1868   A     to balance the load?                                         governor setting      governor setting      decrease the         decrease the        EL-0003
                                                                               on panel 3            on panel 1            voltage regulator    governor setting
                                                                                                                           setting on panel 1   on panel 1

                  A flickering ground detection lamp on a AC electrical        multiple-ground       ground in a coil of   shorted coil in an   short between two
                  power panel could be caused by a __________.                 condition in the      an operating pump     operating            adjacent bars of
12   1869   B                                                                  lighting distribution motor                 ventilation fan      the generator
                                                                               system                                      motor                commutator

                  A general purpose electrical multimeter can be used to       watts                 field flux            current              all of the above
12   1870   C
                  directly measure __________.
                  A four pole, 60 Hz, three-phase synchronous motor            0.0                   1.1                   2.2                  3.3
                  comes up to 1760 RPM when started as an induction
12   1871   A
                  motor. What is the percent slip after the rotor field is
                  energized?
                  In preparing to take insulation resistance readings on a     allow accurate        help the windings release any          help the windings
                  main generator, the windings should be grounded for          zeroing of the        to cool to ambient residual capacitive to cool to the
                  about 15 minutes prior to the test to __________.            meter                 temperature        charge from the     same temperature
12   1873   C                                                                                                           windings            as the ground test
                                                                                                                                            connection

                  For routine cleaning of a commutator, you should apply course sandpaper an emery cloth         a canvas wiper on a fine tooth file to
                  __________.                                            in a slow back and parallel to the axis the commutator    the commutator
                                                                         forth motion       of the commutator while running        while running
12   1874   C                                                            across the
                                                                         commutator slots



                  In the illustrated three phase alternator, line voltage is   1.73 times the        the phase voltage the phase voltage the line current
12   1875   A     equal to __________.                                         phase voltage                           divided by 1.73                              EL-0074

                  Two contributors of electronic console failures are heat     systematic rotation   periodic changing daily inspection of all of the above
                  and vibration. To combat some of their effects,              of circuit cards      or cleaning of      console foundation
                  preventive maintenance procedures should include             with those from       console ventilation bolts
                  __________.                                                  spares to allow       and control room
12   1876   B                                                                  component cooling     air conditioning
                                                                                                     filters



                                                                                 151                                                       Electrical Questions-April 2009
Bk   Num    Ans                           Question                                   Answer A              Answer B             Answer C             Answer D          Illustr
                  Reduced voltage applied to an AC induction motor              result in             lower the starting   cause a greater      increase the
                  during the starting period will __________.                   decreased             current and          starting torque      starting current
12   1877   B                                                                   acceleration time     increase                                  and pump capacity
                                                                                only                  accelerating time

                  Component 'CR1' shown in the illustration is called           Rectifier diode       Zener diode          Varactor diode       Light-emitting
12   1878   B                                                                                                                                                         EL-0085
                  a/an __________.                                                                                                              diode
                  As shown in the illustration, if component 'E1' or 'E2'       burned out rapidly burned out rapidly caused                    is of a lower
                  burns out, the operator will receive an alarm. After          due to its higher  due to its higher  component 'F' to          wattage rating
                  renewing the burned out component, it is found that           voltage rating     wattage rating     burn out                  than required for
                  the alarm still cannot be silenced. The probable cause                                                                        the alarm relay
12   1879   D     for this condition is that the replaced component                                                                             circuit to activate   EL-0058
                  ___________.                                                                                                                  due to insufficient
                                                                                                                                                current flow

                  A hydrometer indicates specific gravity by comparing          density of a          differences in       mass of substance    buoyancy of the
                  the __________.                                               substance in water    weight between       measured with the    indicator in the
                                                                                with the density of   water and the        density of the       liquid being
12   1880   D                                                                   the same              mass of the liquid   same substance       measured as
                                                                                substance in air      being measured                            compared to water

                  Which line in figure "A" represents the instantaneous W                  X                   Y                                Z
12   1881   A                                                                                                                                                         EL-0088
                  value of the wave form shown?
                  When soldering a printed circuit board component, you slowly heating the using the soldering using only acid                  applying
                  should be careful to prevent damage by __________. joints, using a high iron tip sparingly   cord solder                      mechanical
12   1882   B                                                           wattage iron                                                            pressure to the
                                                                                                                                                joints being
                                                                                                                                                soldered
                  The charge of a lead-acid battery is normally checked         manometer             hydrometer           pneumercator         ohmmeter
12   1884   B
                  with a/an __________.
                  The force that causes free electrons to flow in a             resistant force       electromotive        inductive force      dielectric force
12   1885   B     conductor producing electric current is called a/an                                 force
                  __________.
                  Brush sparking in a DC generator during commutation           eddy currents in  laminations in the       excessive brush      coil inductance
                  may be caused by __________.                                  the armature core generator field          pressure             discharge
12   1886   D
                                                                                                  pieces                                        occurring at
                                                                                                                                                commutation
                  The conversion of constant frequency power into               transformers and      rectifiers and       rheostats and        potentiometers
                  adjustable frequency power in a modern AC propulsion          resistors             thyristors           resistors            and diodes
12   1887   B
                  drive system is commonly achieved through the use of
                  __________.
                  An alternator will fail to produce line voltage as a result   a closed circuit      oxidized slip rings improperly        excitation field
12   1888   D     of __________.                                                breaker                                   staggered brushes failure

                                                                                  152                                                        Electrical Questions-April 2009
Bk   Num    Ans                            Question                              Answer A              Answer B          Answer C                    Answer D          Illustr
                  When correcting specific gravity readings of a lead-      always fill the       maintain a load on add correction              subtract correction
                  acid battery for existing temperature conditions, you     battery with acid     the battery when values for battery            values for battery
12   1889   C     should __________.                                        prior to taking       taking readings    temperatures                temperatures
                                                                            readings                                 above 80°F                  above 80°F

                  A single-phase induction motor having a relatively high synchronous             wound-rotor motor capacitor-start              series wound
12   1890   C     starting torque, is the __________.                     motor                                     motor                        compound motor

                  What will be the output frequency of a three-phase, six   60 hertz              90 hertz                120 hertz              180 hertz
12   1891   B     pole, AC generator operating at 1800 revolutions per
                  minute?
                  When a lead-acid battery starts to gas freely after       slightly increased    shut off                decreased to a         maintained for an
12   1892   C     receiving a normal charge current, the charging current                                                 trickle charge         additional hour
                  should be __________.                                                                                   current
                  In a compound-wound motor, a portion of the line          shunt field coils     series field coils      interpoles             all of the above
12   1894   D
                  current flows through the __________.
                  The air gap in an induction motor should be               the condition of      axial misalignment excessive wear of excessive
12   1895   C     periodically checked with a feeler gage to indicate       insulation            of the rotor       the bearings      hysterises loss
                  __________.                                               resistance
                  Cartridge type fuses contain meltable elements that       mild steel            aluminum alloy          copper alloy           lead alloy
12   1896   D
                  are generally made from __________.
                  One diode of a single phase, center tap, full-wave        zero                  a rectified half-       a rectified full-      equal to the AC
12   1897   D     rectifier has burned out in a shorted condition.                                wave                    wave                   input
                  Therefore, the output will be __________.
                  Which of the following is true when comparing a           Primary type          Secondary type          Secondary cells        Secondary cells
12   1898   A     primary type and secondary type storage battery?          batteries are not     batteries are not       always contain         always contain
                                                                            rechargeable.         rechargeable.           acid.                  alkaline.
                  The best method used to properly resurface an             turn it down in the   use a fine tooth file   use a hand stone       burnish it with a
                  eccentric commutator on a small DC electric motor is      ship's lathe                                                         commutator stone
12   1899   A
                  to ________.                                                                                                                   while running

                  A lamp is provided with 110 volts and draws a current     12.2 ohms             88.0 ohms               122.2 ohms             137.5 ohms
12   1901   D     of 0.8 amps. What is the resistance of the lamp?

                  If a circuit has resistances of 5, 10, and 20 ohms        1.5 ohms              2.9 ohms                17.5 ohms              35.0 ohms
12   1911   B     connected in parallel, what is the combined resistance
                  of the circuit?
                  What power is consumed by a heating element using a       20 watts              66.67 watts             720 watts              2400 watts
12   1921   D
                  current of 20 amperes at 120 volts?
                  If a shipboard AC generator experiences voltage           an open in the        the brushes             excessive locked- a rotating slip ring
12   1923   A     failure, the cause may be due to __________.              rotor field circuit   shifting out of the     rotor current
                                                                                                  neutral plane

                                                                              153                                                             Electrical Questions-April 2009
Bk   Num    Ans                           Question                            Answer A           Answer B                    Answer C             Answer D          Illustr
                  How many volts are necessary to provide a current of 21 volts              110 volts                   220 volts            240 volts
12   1931   B     10 amperes to a motor with an in-line resistance of 11
                  ohms?
                  A wire is being used as a replacement having twice the four times as great twice as much               the same as the     one-half of the
                  length and one-half the cross-sectional area of the                                                    original resistance original resistance
12   1951   A     original wire. The resistance of this new wire, when
                  compared to that of the original wire, is __________.

                  Chattering of the collector ring brushes on a generator       lubricating brush   reinsulating the     cleaning the         increasing length
12   1953   C
                  may be remedied by __________.                                holders             brushes              collector rings      of pigtail
                  When the current flow in a power transmission line is         is halved           is doubled           is divided by four   remains the same
12   1961   C
                  halved, the power loss __________.
                  An AC circuit has a capacitive reactance of 30 ohms in        8.37 ohms           10.00 ohms           50.00 ohms           70.00 ohms
                  addition to an inductive reactance of 40 ohms
12   1971   B
                  connected in series. What is the reactance of the
                  circuit?
                  A common-emitter circuit has an input voltage of 0.1          20                  40                   400                  4000
                  volt, an output voltage of 2.0 volts, an input current of
12   1981   C
                  0.5 milliamps, and an output current of 10 milliamps.
                  What is the power gain?
                  An open occurring within the field rheostat of an AC          negative deflection positive deflection buildup of            low, but constant
                  generator can be detected by short circuiting its             of the wattmeter    of the wattmeter    alternator voltage    alternator voltage
12   1983   C
                  terminals and observing a __________.                         pointer             pointer

                  A four pole turbo generator is used in conjunction with 40 RPM                    60 RPM               80 RPM               100 RPM
                  a 160 pole propulsion motor. If the generator is turning
12   1991   C
                  at 3,200 RPM, what is the current speed of the
                  propeller?
                  As shown in the illustration, the purpose of item        statically balance       align the rotor to   dynamically          cool the motor
12   2001   D     labeled "Z", in assembly No. 2, is to __________.        the rotor                the stator           balance the rotor                         EL-0001

                  If the excitation of an alternator operating in parallel ispower factor will      power factor will    ampere load will     kilowatt load will
12   2003   B     decreased below normal, its __________.                    change in the          change in the        be greatly           be greatly
                                                                             lagging direction      leading direction    increased            decreased
                  Which of the following actions must be carried out prior Increase the             Decrease the line    Increase the line    Decrease the line
12   2011   A     to closing the alternator circuit breaker according to the alternator voltage.    voltage.             voltage.             frequency.           EL-0002
                  graph shown in the illustration?
                  As shown in the illustration, the function of the switch bus frequency            reactive volt        frequency of either power factor of
12   2021   D     labeled 'PFSW' is to determine the __________.                                    amperes of the       generator           either generator      EL-0003
                                                                                                    bus


                                                                                  154                                                    Electrical Questions-April 2009
Bk   Num    Ans                          Question                                 Answer A              Answer B            Answer C              Answer D                Illustr
                  Which of the following problems will occur if the circuit The rotor of the        Severe cross        The rotor of the    Both alternators
                  breaker of the incoming alternator is closed and it is    loaded alternator       currents will occur incoming            will parallel 180°
12   2023   B     180° out of phase with the loaded alternator when         will hunt.              which could cause alternator will stop. out of phase.
                  paralleling?                                                                      damage.

                  As shown in the illustration, which of the symbols         A                      B                      C                      D
12   2041   A                                                                                                                                                            EL-0005
                  represents a normally closed electrical contact?
                  A loss of field excitation to an AC generator while        absorb more and        lose its load due to   smoke and              lose its load, begin
                  operating in parallel will cause it to __________.         more load due to       the inherent speed     overload due to        to motorize, trip
                                                                             decreased              droop built into the   field flashover as     out on reverse
12   2043   D                                                                armature reaction      governor               residual field flux    power relay, and
                                                                                                                           changes polarity       possibly
                                                                                                                                                  overspeed

                  Which of the following statements is true concerning       The cycles per         Both alternator        The number of          The load must
                  the operation of two alternators in parallel?              second of each         governors must be      field poles must be    always be divided
12   2073   A                                                                alternator are the     set with the same      the same on each       equally between
                                                                             same.                  amount of speed        alternator.            alternators.
                                                                                                    droop.
                  An alternator switchboard has a synchroscope and           The breaker            The breaker            The frequency          A portable phase
                  synchronizing lamps. If the synchroscope is broken,        should be closed       should be closed       meter should be        sequence indicator
                  which of the steps listed is the most essential before     when one               when both              used to determine      must be used to
                  an alternator can be paralleled with the bus?              synchronizing          synchronizing          that the incoming      verify the
12   2083   C                                                                lamp is dark and       lamps are bright.      alternator             information from
                                                                             the other is bright.                          frequency is           the lamps.
                                                                                                                           slightly higher than
                                                                                                                           the bus.

                  According to Coast Guard Regulations (46 CFR),        at least one light in each power                   each charging          all of the above
                  which of the following systems must be arranged so as the steering gear operated                         panel for
12   2087   D     to be energized by the final emergency power source? room                   watertight door              temporary
                                                                                              system                       emergency
                                                                                                                           batteries
                  If the circuit shown in the illustration were energized    The stop push-         The start push-        Contact 'Ma'           Contact 'OL1'
12   2091   B     and operating properly, which of the devices listed        button                 button                                                               EL-0007
                  would be open?
                  The electrical schematic shown in the illustration         across-the-line        primary-resistor       autotransformer        part-winding
12   2131   A                                                                                                                                                            EL-0017
                  represents a/an __________.                                starter                starter                starter                starter
                  As shown in the illustration, which of the following       The motor will         'H-4' will open,       '10L' and '20L' will   'A-1' or 'A-2' will
                  conditions will occur as a result of a momentary loss of   automatically          necessitating a        open,                  open,
                  power?                                                     restart when           manual restarting      necessitating a        necessitating a
12   2141   B                                                                power is restored.     of the motor.          manual restarting      manual restarting      EL-0017
                                                                                                                           of the motor.          of the motor.

                                                                                 155                                                        Electrical Questions-April 2009
Bk   Num    Ans                            Question                                Answer A            Answer B                Answer C           Answer D             Illustr
                  Sparking at the brushes of a DC propulsion motor can         improper brush      improper brush         reversed interpole all of the above
12   2143   D
                  be the result of __________.                                 pressure            seating                polarity
                  If the motor shown in the illustration will not start when   Fuses 'F-1' and 'F- Operating coil "C".    Contacts 'H-1', 'H- Contact 'H-4'.
12   2151   A     "Q" is depressed, which of the listed components             2'.                                        2', and 'H-3'.                              EL-0017
                  should be checked FIRST?
                  When using a megohmmeter to determine which shunt            insulate the field   disconnect each       use a motor driven remove all main
                  field coil is grounded in a DC machine, you must             frame from the       shunt field coil      high capacity      line lead
12   2153   B
                  __________.                                                  ship's hull          before testing        megohmmeter        connections
                                                                                                                                             before testing
                  As shown in the illustration, which listed action will       Contacts 'H-1', 'H- Contact 'H-4'          Operating coil "C" Switch "R" opens.
12   2161   C     occur first when push button "Q" is depressed?               2' and 'H-3' close. closes.                energizes.                                  EL-0017

                  As shown in the illustration, which of the operations        Coil 'CR' closes  Coil "M" opens           Coil "M" closes        Contact "M"
                  listed will happen when the 'jog button' is pushed?          the normally open contact "M".             contact "M".           remains open
12   2171   C                                                                  'CR' contacts.                                                    despite the jog      EL-0010
                                                                                                                                                 button being
                                                                                                                                                 pushed.
                  The most practical method used for resurfacing a             turn it down in the use a grinding rig     use a hand stone       burnish it with
12   2173   B     ship's main propulsion motor commutator is to                ship's lathe                                                      commutator
                  __________.                                                                                                                    stones
                  When the motor shown in the illustration is running and      Coil "M" will now    Coil 'CR' will now    Contact "M" will       Contacts "M" and
12   2181   D     the stop button is pushed, which of the following            be energized.        be energized.         close as contact       'CR' will open.      EL-0010
                  statements will hold true?                                                                              'CR' opens.
                  Which of the following statements describes the effectsIncreasing                 Increasing            Ambient                At 90°F all local
                  of ambient temperature on local action within lead-    ambient                    ambient               temperature has        action virtually
12   2189   A     acid storage batteries?                                temperature                temperature           no effect on local     ceases.
                                                                         increases local            decreases local       action.
                                                                         action.                    action.
                  When an operating motor is connected to the controller 'L1', stop button,         'L1', stop button,    'L1', stop button,     L1', stop button,
                  shown in the illustration the a path of current flow   start button, coil         'CR' and "M"          jog button, 'CR'       start button, 'CR'
                  through the circuit is __________.                     'CR', 'L2'                 contacts, "M" coil,   contact, 'CR' relay,   contact, "M"
12   2191   B                                                                                       'OL contacts, the     'L2'                   contact,'CR' coil,   EL-0010
                                                                                                    'CR' coil in                                 'L2'
                                                                                                    parallel, 'L2'

                  Referring to the illustrated schematic diagram, which of Normally-open            Current flows         Normally-closed        The blowout coils
                  the following statements is true when the motor is       contacts '4-5' are       through the           contacts "R" are       must be closed.
12   2201   B                                                                                                                                                         EL-0011
                  running in the forward direction?                        closed.                  'Reverse' push-       open.
                                                                                                    button switch.



                                                                                 156                                                        Electrical Questions-April 2009
Bk   Num    Ans                           Question                             Answer A                  Answer B           Answer C               Answer D         Illustr
                  Diesel generators #1 and #2 are operating in parallel at Start the                Ascertain cause of Strip the board of     Secure alarms,
                  near full load capacity. Diesel generator #1 suddenly emergency                   the low lube oil   all non-vital          reset reverse
                  trips out mechanically due to low lube oil pressure.     generator.               pressure.          circuits.              power relay, and
12   2203   C     The reverse power relay functions properly and trips                                                                        restart #1 engine.
                  generator #1 electrically off the board. Which of the
                  following actions should you carry out FIRST?

                  If the three-phase motor, shown in the illustrated            Normally-closed     Normally- open       'L1' and 'L3' must   All of the above.
                  schematic diagram, is running in the forward direction,       contacts "4"-"5"    contacts "2"-"3"     be interchanged
12   2211   C                                                                                                                                                      EL-0011
                  which of the following actions must occur before the          must open.          must close.          via the "R"
                  motor will reverse rotation?                                                                           contacts.
                  In the illustrated schematic diagram, which of the listed     An 'either-or'      A mechanical         Blowout coils        A stop button
12   2221   A     devices prevents the forward and reversing coils from         interlock           interlock                                                      EL-0011
                  being energized simultaneously?
                  The schematic diagram shown in the illustration uses          non-renewable       circuit breaker coil overload relay coil thermal overload
12   2231   D                                                                                                                                                 EL-0011
                  symbol "A" to represent a/an __________.                      fuse link                                                    heater
                  To stop the electric motor shown in the illustration, the     coil 'MS' to        contacts 'CR1' and contacts 'MR1',       contacts 'MS1',
12   2241   C     stop button is depressed, causing __________.                 become de-          'MR4' to open        'MR2', and 'MR3' 'MS2', and 'MS3' to EL-0012
                                                                                energized                                to open             open
                  In the illustration shown, coil 'MR' is a __________.         running contactor   rupture (blowout) resistance coil        reversing coil
12   2251   A                                                                                                                                                 EL-0012
                                                                                coil                coil
                  Which of the devices shown in the illustration                Selector switch     Contact 'CR1a'       Contact 'CR2a'      Contact 'CR1D'
                  automatically prevents the simultaneous operation of
12   2271   D                                                                                                                                                      EL-0073
                  the windlass from both master switches?

                  As shown in the illustration, all 'MS' contacts are           operating coils     magnets              manual operation     solenoid switches
12   2281   C     opened and closed by means of __________.                                                              of the master                             EL-0073
                                                                                                                         switches
                  In a 60 Hz AC system, the current will pass through           60 seconds          6 seconds            1 second             .016 of a second
12   2283   D
                  one complete cycle in __________.
                  In the lighting distribution circuit shown in the             Branch lines "1", Branch lines "1"       Branch lines "1", Branch lines "1"
                  illustration, if all switches are closed and fuse 'F2' were   "2", and "3" would and "3" would burn    "2", and "3" would and "3" would go
12   2291   D     to open, which of the following statements is true?           go out             dimly, while          burn dimly         out, while branch      EL-0013
                                                                                                   branch "2" would                         "2" would remain
                                                                                                   burn normally                            lit
                  Three factors responsible for the change in voltage as        armature winding inductance load         coil pitch factor  armature
                  load is applied to an AC generator are: 1) the drop in        speed              drop                                     reactance voltage
12   2293   D
                  resistance in the armature circuit, 2) the change in flux,                                                                drop
                  and 3) the __________.
                  The electrical schematic shown in the illustration         three phase, 450       three phase, 120     single phase, 120 not specified
12   2301   A     indicates the lighting feeder circuit to the lighting      volt, and 60 cycle     volt, and 60 cycle   volt, and 60 cycle                        EL-0014
                  transformer is __________.

                                                                                  157                                                    Electrical Questions-April 2009
Bk   Num    Ans                             Question                              Answer A                Answer B           Answer C                Answer D             Illustr
                  The division of the reactive KVA load between               prime mover            voltage regulators phase balance            proportioner
12   2303   B     paralleled AC generators is initiated by the                governors                                 relay
                  __________.
                  The purpose of the automatic bus transfer shown in          step-down voltage provide                     energize the         provide
                  the illustration is to __________.                          to the lighting    emergency power            emergency            overcurrent
                                                                              distribution panel to the lighting            switchboard from     protection to the
12   2311   B                                                                                    distribution panel         the main             lighting distribution   EL-0014
                                                                                                                            switchboard          panel

                  The electrical diagram shown in the illustration is used    resistance circuit     inductive circuit      step-down circuit    capacitive circuit
12   2321   D                                                                                                                                                            EL-0015
                  to depict a/an __________.
                  Which of the following losses is/are present in every       Winding copper         Core eddy current      Magnetic             All of the above.
12   2323   D
                  direct current generator armature?                          loss                   loss                   hysteresis loss
                  Regarding the illustrated electrical schematic, 'S1-P',     capacitors             normally-closed        normally-open        normally-closed
12   2331   C     'S1-Q', and 'S1-R' represent __________.                                           contacts               contacts             pushbutton              EL-0016
                                                                                                                                                 switches
                  If fuse 'F-1' in the illustrated schematic diagram opens, the motor will run       'A-1' and 'A-2' will   the motor will not   the start button will
12   2341   C     __________.                                               slowly                   open                   start                jam in the closed       EL-0017
                                                                                                                                                 position
                  Upon failure of the normal power supply, the                bus tie feeder         automatic bus          line connection      power failure
12   2343   B     emergency generator is placed on the line by the                                   transfer device        feeder               alarm bus
                  __________.
                  The electrical diagram shown in the illustration            series-wound           shunt-wound            compound-wound       flat-compounded
12   2351   C                                                                                                                                                            EL-0054
                  represents a __________.                                    motor                  motor                  motor                motor
                  The most common type of AC service generator found          electromagnetic        electromagnetic        armature,            armature, rotating
                  aboard ship is the stationary __________.                   field, revolving       field, oscillatory     oscillatory          electromagnetic
12   2353   D
                                                                              armature type          armature type          electromagnet        field type
                                                                                                                            field type
                  The load sharing characteristics of two diesel              load limit             idle speed             speed limit          speed droop
                  alternators operating in parallel are directly related to
12   2363   D
                  the setting of their governors' __________.

                  As shown in the illustration, if 'R1' and 'R2' have         voltage drop           current flow           the energy           current flow
                  unequal ohmic values, the __________.                       across 'R1' will not   through 'R1' will      dissipated in 'R1'   through 'R1' will
                                                                              be equal to the        equal the current      will be the same     differ from the
12   2371   D                                                                 voltage drop           flow through 'R2'      as the energy        current flow            EL-0019
                                                                              across 'R2'                                   dissipated in 'R2'   through 'R2'



                  Which of the following statements is correct for the        'R1', 'R2', and 'R3' 'R1', 'R2', and 'R3' The voltages             The total
                  illustrated circuit?                                        are connected in are connected in measured across                  resistance equals
12   2391   A                                                                 series.              parallel.            'R1', 'R2', and 'R3'     1/R1 + 1/R2 +           EL-0020
                                                                                                                        are equal.               1/R3.

                                                                                158                                                           Electrical Questions-April 2009
Bk   Num    Ans                          Question                                  Answer A             Answer B              Answer C                Answer D           Illustr
                  The electrical diagram shown in the illustration shows      'R1', 'R2', and 'R3' 'R1', 'R2', and 'R3' the voltages             the total resistance
                  __________.                                                 are connected is are connected in measured across                  equals R1 + R2 +
                                                                              series               parallel             'R1', 'R2' and 'R3'      R3
                                                                                                                        will be different if
12   2401   B                                                                                                           'R1', 'R2' and 'R3'                             EL-0021
                                                                                                                        have different
                                                                                                                        values

                  The electrical schematic illustrated in figure A, depicts autotransformer Delta Wye                      primary EMF           potential
12   2411   D                                                                                                                                                           EL-0059
                  a/an __________.                                                          transformer                    generator             transformer
                  Which of the following statements about a three-phase The line current is The phase current              The line voltage is   The phase voltage
                  wye connection is correct?                                1.73 times the  is 1.73 times the              1.73 times the        is 1.73 times the
12   2413   C
                                                                            phase current.  line current.                  phase voltage.        line voltage.

                  Which of the following statements is true concerning        Terminal 'T2' is hot Both indicating         Overload              'L2' is always
                  the motor controller diagram shown in the illustration?     only on high         lights will be lit on   protection is         connected to 'T2'
                                                                              speed.               both high and low       provided for high     whenever the
                                                                                                   speeds as they          speed operation       motor is running.
12   2421   D                                                                                      are connected to        only.                                        EL-0023
                                                                                                   the common lead
                                                                                                   when the motor is
                                                                                                   running.

                  As shown in the illustration, the generator field is        conductors "1", "2" inductor 'L1'            rectifier 'CR1'       winding 'S-2'
12   2423   C                                                                                                                                                           EL-0016
                  excited with DC current provided by __________.             and "3"
                  The wiring diagram for the motor starting circuit shown     resistance starting reduced voltage          low voltage           low voltage
12   2431   C                                                                                                                                                           EL-0007
                  in the illustration indicates __________.                                       starting                 protection            release
                  As shown in the illustration, part "X" of the diagram is    commutator          interpole                starting pole         auxiliary pole
12   2433   B                                                                                                                                                           EL-0052
                  known as a/an __________.
                  The graph shown in the illustration represents the          by unit "A"           by unit "B"            equally by each       none of the above
                  speed droop curves of two equal capacity alternators                                                     unit
                  about to be paralleled. When paralleled, the greater
12   2441   A     portion of the total load above 60% for each unit will be                                                                                             EL-0025
                  picked up __________.

                  What would be the reaction of a generator                   Revolve slowly in Revolve rapidly in Revolve rapidly in Remain stationary
                  synchroscope pointer when indicating the phase              the slow direction. the slow direction. the fast direction. at the 12 o'clock
12   2443   C                                                                                                                                                           EL-0002
                  relationship shown in the following illustration?                                                                       position

                  As shown in the illus