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CAT. F4-98 - Microener

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CAT. F4-98 - Microener Powered By Docstoc
					AUTOMATIC LOAD SHARING CONTROL FOR
GENERATORS WORKING IN PARALLEL
                                                                                         MICROELETTRICA SCIENTIFICA

                                                                             RRS              MILANO    ITALY




                                                                                         CAT. F4-98
                                                                                                              01-10-98


!   Automatic active or reactive power sharing with frequency control

!   Automatic load shedding

!   Over power element


                  GENERAL CHARACTERISTICS
The relay RRS features the automatic sharing of the active or reactive power
supplied by two or more generators working in parallel, in a stable an efficient
way, due to the accuracy and the repeatability of its setting and to the high
insensitivity to interferences and disturbance. Active Load sharing is made by
proper “increase” or “decrease” signals sent by the contacts of two relays to the
fuel injection control unit of generator’s engine; when used for reactive load
sharing, the output signals are sent to the voltage regulator. The duration of the
output pulses and the time interval between two pulses are adjustable, thus
allowing the best coordination with the generator response-time. To control the
load sharing the unit measures the power supplied by each generator as well as
the average power of the system (i.e. total supplied power divided by the n° of
generators working in parallel). The power supplied by each generator is then
compared with the average power and, if the first is higher or lower than the
second, the unit gives-out proper signals to the controlled generator.
Furthermore a frequency measurement combined with the power one, makes all
the system work at the rated frequency, operating so that even if one of the
generators is more loaded than the others but the system frequency is under the
rated, the load sharing is made by loading more the other generators, to
increase the frequency of the system. The power and frequency sensitivity of
the RRS are pre-set (standard setting: ∆W≅4%; ∆F≅0.5Hz)
The unit also includes an “over power”, element which trips when the power
supplied by the generator exceeds its rating. Another element activated via the
terminals 21-22 provides a smooth load shedding. One unit RRS is provided for
each generator and the connection is made via one C.T. and one V.T. of the                   ORDERING
controlled generator (on request, voltage connection can be direct up to                   INFORMATION
380/440V – 50/60Hz).

Auxiliary voltage is supplied to an internal multivoltage unit fully isolated.       !   Rated input voltage
The unit is modular on standard European size withdrawable P.C. board with           !   Rated input current
51mm wide front: version “E” for flush mounting complete with accessories for
protruding mounting and “E R” for 19” 3U rack mounting are available.                !   Auxiliary supply voltage

                                                                                     !   Mounting execution




                                                                                         Cat. F4-98 - RRS – R1 – 1/4
                                      SIGNALIZATION

!   LED       Green    NORMAL         : Lit-on indicates unit’s normal operation
!   LED       Red      LOAD SHARING   : Lit-on indicates that the Load Sharing function is active
!   LED       Yellow   FREQ. CONTR.   : Lit-on indicates that the Frequency Control function is active
                                       Dip-switch to set the duration required for the “Increase power” or
!   CONTROL PULSE DURATION             “Decrease power” pulse. The output contact of the corresponding
                                       relay (when operated) remains closed for the time T
                                                 T = 0.1 + Σt (sec.) = [0.1÷1.6 sec.] step 0.1 sec
                                       Dip-switch to set the duration To of the time interval between two
!   CONTROL PULSE PAUSE
                                       subsequent load variation pulses.
                                                    T = 1 + Σto (sec.) = [1 ÷ 16 sec.] step 1 sec
                                       Dip-switch to set the generator rated power related to the secondary
!   Wg / Wn
                                       side of input transformers.
                                        Wg   gerator' s rated Volt   generator' s rated current
                                           =                       x
                                        Wn VT' s primary rated Volt CT' s primary rated current
                                                    Wg / Wn = 0.25 + ΣW = [0.25 ÷ 1] step 0.05
                                       Dip-switch for selection of relay operation as active load sharing or
!   ACTIVE / REACTIVE POWER
                                       reactive load sharing
                                       Dip-switch for locally activate / disactivate the frequency control
!   FREQUENCY CONTROL
                                       function; remote operation via terminals 10-11
                                       Dip-switch for locally activate / disactivate the Load Shedding
!   LOAD SHEDDING
                                       function; remote operation via terminals 21-22
!   OPERATION                          Dip-switch for locally activate / disactivate relay operation
                                       Led red: it indicates that the unit is giving-out a “Increase Power”
!    ↑
    W↑+
                                       signal by closing the contact of the relevant output relay.
                                       Led red : it indicates that the unit is giving-out a “Decrease Power”
!    ↓
    W↓-
                                       signal by closing the contact of the relevant output relay.


                                  OVERALL DIMENSIONS




                                                                                         Cat. F4-98 - RRS – R1 – 2/4
                                         WIRING DIAGRAM




!   When the relay in used in association with an automatic synchronizing unit, the frequency control must be
    disactivated until the generator is connected in parallel (switched-on).

!   When 2 or more relay control different generators, the frequency control must be operating only on the unit
    associated to the generator selected as main generator (pilot generator) and disactivated on all the other units.



                                     AUXILIARY POWER SUPPY


!   Type 1 = 24(-20%)-110(+20%)Vac / 24(-20%)-125(+20%)Vdc

!   Type 2 = 80(-20%)-220(+20%)Vac / 90(-20%)-250(+20%)Vdc


                                             CABLE WIRING

Terminals     1-2       :   Decrease power output contact
Terminals     4–5       :   Voltage input
Terminals     6-7       :   Current input
Terminals     8-9       :   Power supply input
Terminals    10 - 11    :   Frequency control operative when contact is closed
Terminals    12 - 13    :   Increase power output contact
Terminals    14 - 15    :   Interconnection with other load sharing units
Terminals    17 - 18    :   Over power output contact
Terminals    21 - 22    :   Automatic load sharing operative when contact is open




                                                                                              Cat. F4-98 - RRS – R1 – 3/4
                                     ELECTRICAL CHARACTERISTICS

!   Conform to standards                                           CEI 41-1; IEC255; CE
!   Rated insulation level                                         600V
!   Dielectric test voltage                                        2kV – 50Hz – 1min.
!   Surge test                                                     5k Vp – 1.2/50µsec.
!   Operational temperature                                        -10 / +50°C
!   Interference test                                              2.5 e 1 kV – 1MHz
!   Rated input voltage                                            up to 380V – 50Hz; 440V – 60Hz
!   Rated input current                                            1 or 5A
!   Voltage burden                                                 0.5 VA
!   Current burden                                                 0.35 VA at In
!   Max power supply consumption                                   7 VA
!   Power setting range                                            (0.25 – 1) Wg/Wn
!   Load sharing insensitivity                                     1 – 5 % Wn (presetted at 4%)
!   Frequency control insensitivity                                ± 0.5Hz presetted
!   Setting range of output pulses duration                        t = 0.1 – 1.6 sec
!   Setting range of output pulses pause duration                  to = 1 – 16 sec.
!   Output relay                                                   3 energizing on operation
!   Output relays contacts 1 N/O for each relay                    Rated Current 5A; Vn = 380V
                                                                   Rated a.c resistive switching
                                                                   power = 1100W (max 380V)
                                                                   Make = 30A (peak) for 0.5 sec.
                                                                   Brake = 0.3A 110 Vc.c.
                                                                   L/R = 40ms (100.000 ops.)




                 Microelettrica Scientifica S.p.A. - 20089 Rozzano (MI) - Italy - Via Alberelle, 56/68
                      Tel. (##39) 2 575731 - Fax (##39) 2 57510940 - Telex 351265 MIELIT I

                                               http://www.microelettrica.com
    The performances and the characteristics reported in this manual are not binding and can modified at any moment without notice




                                                                                                            Cat. F4-98 - RRS – R1 – 4/4

				
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