# EXPT NO MEASUREMENT OF RESISTANCE USING WHEATSTONE BRIDGE

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```					MEASUREMENTS AND INSTRUMENTATION
LABORATORY –EE 2208
LIST OF EXPERIMENTS

S.NO                TITLE                 PAGE NO

1
MEASUREMENT OF RESISTANCE USING
WHEATSTONE BRIDGE
2      MEASUREMENT OF RESISTANCE USING
KELVIN’S DOUBLE BRIDGE.
3     MEASUREMENT OF CAPACITANCE USING
SCHERING BRIDGE.
4     MEASUREMENT OF INDUCTANCE USING
MAXWELLS BRIDGE.
5      CALIBRATION OF 1 ENERGYMETER.

6     MEASUREMENT OF 3 PHASE POWER AND
POWER FACTOR
7        INSTRUMENTATION AMPLIFIER.

8     STUDY OF DISPLACEMENT TRANSDUCER
- LVDT
9       STUDY OF PRESSURE TRANSDUCER

10             A/D CONVERTER

11             D/A CONVERTER

12          STUDY OF TRANSIENTS

13         CALIBRATION OF CURRENT
TRANSFORMER
14        MEASUREMENT OF IRON LOSS
(MAXWELL BRIDGE)
EXPT NO 1

MEASUREMENT OF RESISTANCE USING WHEATSTONE BRIDGE

AIM :
To measure the given medium resistance using Wheatstone Bridge.

OBJECTIVE :
1.      To study the working of bridge under balanced and unbalanced condition.
2.      To study the sensitivity of bridge.
EQUIPMENT :
1.      Wheat stone Bridge kit            – 1 No
2.      Unknown resistance                – 1 No
3.      Multimeter                        – 1 No
4.      Connecting Wires.

CIRCUIT DIAGRAM :

P                    Q

G
S
Rx                  S

EXERCISE :
1.      Design a bridge for the given parameters.
2.      Find the unknown resistance.
3.      Find the sensitivity of Bridge.
PROCEDURE:

1.The resistance to be measured is connected between XX points in the bridge kit.
2.The P/Q ratio (multiplier) is initially kept at position ‘1’ and the deflection of the
galvanometer is observed by pressing both the battery and the galvanometer keys.
3.The S arm (X 1000) is adjusted and two positions are identified for which the
deflection of the galvanometer is on either side of the null point and kept at the lowest
value of S. Then the x100, x10, x1 knobs of S are adjusted to get null deflection. If
necessary the sensitivity knob may be controlled to get appreciable deflection. [If not
possible P/Q ratio is kept at suitable value ie, any one of ratios provided.]
4.The value of unknown resistance is read. (S value)
5.Steps 3 and 4 are repeated for some other P/Q ratio. The mean value is taken.
6.The experiment is repeated with other samples provided.
The above experiment may be used for measuring resistance of the samples less
than 1 to greater than 10000 with lesser sensitivity.

TABULAR COLUMN:

S.NO           SAMPLE        P/Q RATIO                S VALUE        UNKNOWN
(MULTIPLIER)                 ()         RESISTANCE
RX ()

CALCULATION:

Unknown Resistance, Rx = P/Q * S ()
Where P, Q = Ratio Arms.
S = Variable resistance,
Rx = Unknown resistance.
VIVA VOCE :

1.

RESULT: The value of unknown resistance is, Rx =
EXPT NO 2

MEASUREMENT OF RESISTANCE USING KELVIN’S DOUBLE BRIDGE.

AIM
To measure the given low resistance using Kelvin’s double bridge method.

OBJECTIVE
1.      To study the working of bridge under balanced and unbalance condition.
2.      To study the sensitivity of bridge.

EQUIPMENT
1.      Kelvin Double bridge kit       – 1 No
2.      Unknown resistance             – 1 No
3.      Multimeter                     – 1 No
4.      Connecting wires.

CIRCUIT DIAGRAM:

P            Q

p            q

Rx                            S

a        m                    n       c

FORMULA USED:

Rx = P/Q * S ohms
Where
P,Q  First set of ratio arms.
P,q  Second set of ratio arms.
S  Standard resistance,
Rx  unknown resistance.
EXERCISE
1.     Design a bridge for the given parameters.
2.     Find the unknown low resistance.
Find the sensitivity of bridge
PROCEDURE:

1.The resistance to be measured is connected such that the leads from +C and + P are
connected to one end and those from –C and –P are connected to the other end in the kit.
2.The P/Q ratio (multiplier) is initially kept at position ‘1’ and the deflection of the
galvanometer is observed by pressing the galvanometer key.
3.The ‘S’ arm (main dial) is adjusted and two positions are identified for which the
deflection of the galvanometer is on either side of the null point. [If not some other P/Q
ratio is to be tried].
4.The lowest of the two position indicates the coarse value of the unknown resistance and
the null point is obtained by adjusting the Vernier scale, with the galvanometer sensitivity
knob at the maximum position.
5.The value of unknown resistance is read. [‘S’ Value]
6.Steps 3,4,5 are repeated for some other P/Q ratio for the unknown resistance. The mean
value is taken.
7.The above procedure is repeated with another sample.

TABULAR COLUMN:

S.NO             SAMPLE           P/Q RATIO         S VALUE
(Multiplier)                           UNKNOWN
COARSE       FINE      RESISTANCE
()         (        RX ()

3.     .
VIVA VOCE :

1.
RESULT:

The value of unknown resistance is found experimentally.
Values measured (Rx) are,
1.
2.
EXPT NO 3

MEASUREMENT OF CAPACITANCE USING SCHERING BRIDGE.

AIM :
To measure the unknown capacitance using Schering bridge.

OBJECTIVE :
1.      To measure the unknown capacitance.
2.      To study about dissipation factor.

EQUIPMENT :
1.      Schering Bridge kit            – 1 No
2.      Multimeter                     – 1 No
3.      Unknown capacitance            – 1 No
4.      Connecting wires

CIRCUIT DIAGRAM :

r1              R3

C1
D

C4

C2
R4

EXERCISE
1.      Design a bridge circuit for the given parameters.
2.      Find the dissipation factor.
3.      Fluid the unknown capacitance.
R2 = Non-Inductive Variable Resistor
PROCEDURE:

1.Connections are given as shown in the circuit diagram.
2.The value of R2 is selected arbitrarily (say1K) and R1 is varied.
3.If the selection of R2 is correct the balance point (NULL POINT) can be observed on
the oscilloscope by varying R1.If not another value of R2 is chosen.[At balance the
vertical line in the oscilloscope comes to a point for an particular value of R1 in the same
direction.]
4.The capacitor C1 can be varied for fine balance adjustment.
5.When the balance condition is reached, the trainer kit is switched OFF and the value R1
is measured using a multimeter.
6.The value of unknown capacitance is calculated.
7.The experiment is repeated for various samples provided.

TABULAR COLUMN:

S.NO           SAMPLE           R2              R1           UNKNOWN
()              ()           CAPACITANCE

CALCULATION:

Unknown capacitance, Cx = R1/R2 * C3,
Where C3 = Known Capacitance, Microfarads

VIVA VOCE :

1.

RESULT:

The value of unknown capacitance is found experimentally by using the
Schering bridge.
Unknown Capacitance, Cx =
EXPT NO 4

MEASUREMENT OF INDUCTANCE USING MAXWELLS BRIDGE.

AIM
To find the unknown inductance and Q factor of a given coil.

OBJECTIVE
1.   To find the unknown inductance of the given coil using bridge circuit.

2.     To study that Maxwell inductance, capacitance bridge is suitable for the
measurement of law Q coils.

EQUIPMENT
1. Maxwell’s inductance Capacitance Bridge kit – 1 No
2. Multimeter                                  – 1 No
3. Unknown Inductance                          – 1 No
4. Connecting wires

CIRCUIT DIAGRAM :

L1
R3
R1
D
C4

R2
R4

EXERCISE
1.  Design a bridge circuit for the given parameters.

2.     Find Q factor of the coil.
3.     Find unknown Inductance.

PROCEDURE:

TABULAR COLUMN:

S.NO          SAMPLE          R4             C4          UNKNOWN
INDUCTANCE

CALCULATION:
R1=R2R3/R4
Unknown Inductance L1=R2xR3xC4 Henry
Thus we have two variables R4 and C4 which appears in one of the two balance equation
and hence the two equation are independent , and balance is obtained by varying R4and
C4 alternately
The expression for Q factor
Q=L1/R1=C4R4

VIVA VOCE :

1.

RESULT:
The value of unknown capacitance is found experimentally by using the
Schering bridge.
Unknown Capacitance, Cx =
EXPT NO 5

CALIBRATION OF 1 ENERGYMETER.

AIM:

To calibrate the given single phase energy meter at unity and other power factors

OBJECTIVES
1.       To study the working of energy meter
2.       To accurately calibrate the meter at unity and other power factor
3.       To study the % of errors for the given energy meters
EQUIPMENT
1.       Energy meter          – 1 No
2.       Wattmeter             – 1 No
3.       Stop watch             – 1 No
4.       M.I Ammeter           – 1 No
5.       M.I Voltmeter         – 1 No
CIRCUIT DIAGRAM:

P                     (0-10)A
10A                       M                     L       C1                  C2
FUSE                            R1       L1                 R1       L1
1        1
2              2   1        1
2           2
1k       10uH               1k       10uH
C                    V           P1              P2

10A
FUSE
N
NAME PLATE DETAILS:

RATED CURRENT

RATED VOLTAGE

FREQUENCY

REVOLUTIONS/KWH

APPRATUS REQUIRED:

S.NO    NAME OF THE APPRATUS       RANGE   TYPE   QTY
EXERCISE
1.      Measure the experimental energy consumed
2.      Calculate the theoretical energy
3.      Calculate the percentage of error
4.      Draw the calibration curve

PROCEDURE:

1.Connections are given as shown in the circuit diagram.
2.Supply is switched ON and load is increased in steps, each time noting the readings of
ammeter and wattmeter. Also the actual time taken for 1 revolution of the disc is
measured using stop watch.
3.Step 2 is repeated till rated current of the energy meter is reached.
4. % Error is calculated and calibration curve is drawn.

TABULAR COLUMN:

I              (Sec)     W1
(Amps)                  (watts)

CALCULATION:
Let x revolution / kwh be the rating.
Now x revolution = 1 kwh
= 1* 3600*1000* watt-sec.
Constant k of energymeter = 3600 * 103/x watt-sec
For each load indicated power Wi is given as Wi = k/t watts
Where
K= energymeter constant (watt-sec)
T= time for 1 revolution(sec).
Actual power is indicated by the wattmeter reading.
% error = Wi-Wa/Wi* 100.
It can be zero +ve or –ve.
MODEL GRAPH:

+Ve
% Error
0
Wi

-Ve

VIVA VOCE :
1.

RESULTS:

From the calibration curve it is possible to predict the error
in recording the energy. So the correction can be applied to the energy meter
EXPT NO 6

.       MEASUREMENT OF 3 PHASE POWER AND POWER FACTOR

AIM
To conduct a suitable experiment on a 3-phase load connected in star or delta to
measure the three phase power and power factor using 2 wattmeter method.

OBJECTIVES
1.           To study the working of wattmeter
2.           To accurately measure the 3 phase power
3.           To accurately measure the power factor
4.           To study the concept of star connected load and delta connected load

EQUIPMENT
1.           3 phase Auto transformer     – 1 No
2.           M.I Ammeter                  – 1 No
3.           M.I Voltmeter                – 1 No
4.           Wattmeter                    – 1 No
CIRCUIT DIAGRAM:

600 V,10A,UPF
(0-10)A
R                       10 A             M                           L
A
FUSE
R1       L1
1          2

C   R
10uH
V
3 PHASE
Y                     10 A
FUSE

R1       L1
1          2
C            10uH       V
B                     10 A                   R

FUSE
M                               L

600 V,10A,UPF
EXERCISE
1.      Measure the real power, reactive power and power factor of 3 phase resistive
2.      Measure the real power, reactive power and power factor of 3 phase resistive

PROCEDURE:

1.Connection are made as per the circuit diagram, Keeping the inductive load in the
initial position.
2.Supply switch is closed and reading of ammeter and wattmeter are noted .If one of the
wattmeter reads negative, then its potential coils (C and V) are interchanged and
3.The above procedure is repeated for different values of inductive coil. Care should

be taken that current should not exceed 10A during the experiment.

TABULAR COLUMN:

S.NO              I                W1            W2           POWER          P.F
P
(Amps)            (Watts)       (Watts)       Watts         COS

FORMULA USED:

1. Total power P = W1+W2 (W)
2.  = Tan-1 3[W1-W2/W1+W2]
3. P.F = Cos.

VIVA VOCE :

1.

RESULT:
The Power and Power factor of the given coil is measured by using only two
wattmeters.
EXPT NO 7

INSTRUMENTATION AMPLIFIER.

AIM:
To study the working of instrumentation amplifier.

OBJECTIVE:

1.     To study the characteristic of operational amplifier.
2.     To study the use of operational amplifier as instrumentation amplifier.

EQUIPMENT :

1.     Operational Amplifier         – 1 No
2.     Resistors                     – 1 No
3.     RPS                           – 1 No
4.     Voltmeter                     – 1 No
5.     Multimeter                    – 1 No
6.     Connecting wires.

CIRCUIT DIAGRAM:

EXERCISE:

1.     Measure the output voltage for varying input voltage.
2.     Calculate the output voltage theoretically.
3.     Calculate the error.
PROCEDURE:

1.Connect an external power supply with 12v DC must be connected to the load coming
out of instrument.
2.Connect the different signal from circulating to v1 & v2 of the channel with you want
use.
3.Switch on the power supply connected to ties & the circuit that you are likely to
connect the instrument.

TABULAR COLUMN:

V1   (v)       V2 (v)         Vout (v)

RESULT:

Thus the instrumentation amplifier is studied experimentally.
EXPT NO 8

STUDY OF DISPLACEMENT TRANSDUCER - LVDT

AIM
To study the operation of LVDT

OBJECTIVES
1.    To study the basic principle of LVDT.

2.    Study of signal conditioning circuit.

3.    Study of LVDT as transducer.

EXERCISE
1.    Draw the characteristic curve for a given LVDT.

2.    Find the residual voltage.

3.    Fluid the non-electrical quantity displacement interms of voltage.

EQUIPMENT
1.    LVDT kit       – 1 No
2.    Multimeter     – 1 No

TABULAR COLUMN:
S.NO DISPLACEMENT                DISPLACEMENT      MULTIMETER
MICRO-METER                 (mm)              (Volts)
(mm)
MODEL GRAPH:

Absolute
Volts

PROCEDURE:
1. Adjust the micrometer to read 200m of micrometer figure. This position is
called as end of transducer position.
3. Now adjust the micrometer jig. This position is called negative end of
transducer position.
4. No need to adjust any further for this as the displacement automatically
5. Repeat steps 3 and 4 repeatedly till we get the absolute value.

CIRCUIT DIAGRAM:

AC Excitation

Primary Winding

Displacement                                   CORE

ES1                          ES2

E0
SCHEMATIC DIAGRAM:
Primary Winding (P1)

Secondary Winding (S1)                                                          S2

SOFT IRON
Arm Displace
CORE
-ment               A

RESULT:
Thus the displacement is found using LVDT and hence the output is verified
using different graphs.
EXPT NO 9

STUDY OF PRESSURE TRANSDUCER

AIM
To study the operation of bourdon tube

OBJECTIVES
1.    To study the basic principle of Bourdon tube.

2.    Study of Bourdon tube as transducer.

EXERCISE
1.    Draw the characteristic curve for a given Bourdon tube i.e. pressure vs. o/p (V or
I).

2.    Measure the non-electrical quantity pressure interms of voltage or current.

EQUIPMENT
1.    Bourdon pressure transducer kit – 1 No
2.    Foot pump                       – 1 No
3.    Voltmeter                     – 1 No
4.    Multimeter                    – 1 No
EXPT NO 10

A/D CONVERTER

AIM
To design and test a 4 bit A/D converter

1.     Successive approximation type
2.     Ramp type

OBJECTIVE
1.     To study the conversion of analog I/P voltage to digital o/p voltage.
2.     To study the operation and characteristic of operational amplifier

EQUIPMENT
2.     IC 741               – 1 No
3.     DC trainer kit                – 1 No
4.     RPS                  – 1 No
5.     Resistor             – 1 No
6.     CRO                           – 1 No

CIRCUIT DIAGRAM:

EXERCISE
2.     Verify the practical output with theoretical output

PROCEDURE:
VIVAVOCE:

RESULT:
EXPT NO 11

D/A CONVERTER

AIM
To design and test a 4 bit D/A converter

1.      Weighted resistor technique
OBJECTIVE
1.      To study the conversion of binary voltage to analog o/p voltage
2.      To study the operation and characteristic of operational amplifier

EQUIPMENT
7.     IC 741                – 1 No
8.     DC trainer kit                 – 1 No
9.     RPS                   – 1 No
10.    Resistor              – 1 No
11.    CRO                            – 1 No

CIRCUIT DIAGRAM:

EXERCISE
1.      Given 4 bit binary input is converted to analog output
2.      Verify the practical o/p with theoretical o/p

PROCEDURE:
VIVAVOCE:

RESULT:

D/A CONVERTER

AIM
To convert the given digital input into its equivalent analog output.
OBJECTIVE
3.          To study the conversion of binary voltage to analog o/p voltage
4.          To study the operation and characteristic of operational amplifier

EQUIPMENT
IC 741                     – 1 No
Resistor     1K           – 2 No
2.2k         – 7 No
100          –1 No
Multimeter                 –1No
Dual Power Supply          (0-30)V       1No
Bredboard & Connecting Wires
CIRCUIT DIAGRAM:

PROCEDURE:

i.        Make the connections as per the circuit diagram
ii.       Apply the binary input by closing appropriate switches
iii.      Measure the analog output using a multimeter
iv.       Tabulate the measured values
v.      Plot a graph between digital input Vs analog output and digital input Vs
% output
RESULT:
Thus the given digital input is converted into its equivalent analog output.

EXPT NO 12

STUDY OF TRANSIENTS

AIM
To study the transient response of the given system

OBJECTIVE
1. To study the transient behaviour of the given system
2. To study the effects of transients
EQUIPMENT

1. Resistance         – 1 No
2. Capacitance        – 1 No
3. RPS                – 1 No
4. Voltmeter – 1 No
5. Multimeter         – 1 No

CIRCUIT DIAGRAM:

EXERCISE
1. Draw the response curve for the given system
2. Find the time when the error is minimum

PROCEDURE:
VIVAVOCE:

RESULT:

EXPT NO 13

CALIBRATION OF CURRENT TRANSFORMER

AIM
To study the working of current transformer

OBJECTIVE
1.      To study the current transformation concept
2.      To study the efficiency of a given current transformer
3.      To study the loss components in the circuit
EQUIPMENT
1. Current Transformer – 1 No
2. Lamp Load             – 1 No
3. Voltmeter             – 1 No
4. Ammeter               – 1 No

CIRCUIT DIAGRAM:

EXERCISE
1. Draw the curve primary current Vs secondary current
2. Observe the o/p for lamp load
3. Calculate the efficiency
PROCEDURE:

VIVAVOCE:
RESULT:

EXPT NO 14

MEASUREMENT OF IRON LOSS (MAXWELL BRIDGE)

AIM
To determine the iron losses in magnetic material using bridge method

OBJECTIVE
1. To study about hysterisis loss
2. To study about eddy current loss
EQUIPMENT
1.    Maxwell bridge set up        – 1 No
2.    Ring specimen                – 1 No
3.    Ammeter                      – 1 No
4.    Galvanometer                 – 1 No

CIRCUIT DIAGRAM

EXERCISE

1.    Measure the current
2.    Calculate iron loss
3.    Calculate AC permeability
4.    Draw phasor diagram
PROCEDURE:

RESULT

A/D CONVERTER
AIM

OBJECTIVE
3.    To study the conversion of analog I/P voltage to digital o/p voltage.
4.    To study the operation and characteristic of operational amplifier
EQUIPMENT
Op Amp       LM741           -3No
Resistors    470            -3No
1K             -4No
LED                          -3No
RPS          (0-5V)          -1No

CIRCUIT DIAGRAM:

EXERCISE
4.    Verify the practical output with theoretical output

PROCEDURE:
i.   The connections are made as shown in diagram
ii.  The voltage is increased in steps.The analog input is also given
iii. The truth table is verified

RESULT:

Thus the analog to digital convertor was implemented and the truth table verified

.   EXPT NO 12
STUDY OF TRANSIENTS
RC TRANSIENTS:

AIM
To Observe and plot the transients waveform for a series RC circuit and compute
the time constant.
OBJECTIVE
3. To study the transient behaviour of the given system
4. To study the effects of transients
EQUIPMENT

6. Resistance          – 1 No
7. Capacitance         – 1 No
8. Signal Generator
9. CRO & Probes
10. Bred board & Connecting Wires

NOTE
Choose the frequency (f) in signal generator such that f < (4z)^-1 where Z=RxC

CIRCUIT DIAGRAM:

EXERCISE
3. Draw the response curve for the given system
4. Find the time when the error is minimum

PROCEDURE:
i.            Make the connections as per the circuit diagram
ii.           Choose square wave made in signal generator and apply a
suitable input
iii.   Observe and plot the output waveform
iv.    Calculate the time required by output to reach 0.368 times the
input value(peak)
v.     This value given practical time constant
RESULT:
Thus the transient nature of RC circuit has been studied and the waveform plotted

RL TRANSIENTS:

AIM:
To observe and plot the transient waveform for a series RL circuit and
compute the time constant

OBJECTIVE
5. To study the transient behavior of the given system
6. To study the effects of transients
EQUIPMENT

Resistance                1KOhm       – 1 No
Inductor                  10mH        – 1 No
Signal Generator
CRO & Probes
Bred board & Connecting Wires

NOTE
Choose the frequency (f) in signal generator such that f < (4z)^-1 where Z=L/R
PROCEDURE:
i.       Make the connections as per the circuit diagram
ii.      Choose square wave made in signal generator and apply a
suitable input
iii.     Observe and plot the waveform
iv.      Calculate the time required by output to reach 0.632 times
the input value(peak)
v.       This value given practical time constant

RESULT:
Thus the transient nature of RL circuit has been studied and the waveform plotted

EXPT NO 14

MEASUREMENT OF IRON LOSS (MAXWELL BRIDGE)

AIM
To Measure the iron loss of a given ring specimen
OBJECTIVE
3. To study about hysterisis loss
4. To study about eddy current loss
EQUIPMENT:
    Ring Specimen
    Measurement of iron loss trainer
    CRO

CIRCUIT DIAGRAM

PROCEDURE:

1. Patch the circuit as per the circuit diagram
2. Connect the ring specimen to the corresponding connector provided on the
front panel left corner
3. Switch ON the trainer observes the CRO output which should be some value
4. We have to null this output for that adjust the R value by using both fine and
5. Further adjust the L value until the Vout get a null condition.
6. Observe the ammeter value
7. Switch OFF the trainer
8. Measure the R value, L value using multimeter

RESULT:
The iron loss of the given ring specimen was calculated by using Maxwell’s Bridge.
INSTRUMENTATION AMPLIFIER

AIM:
To obtain the frequency response characteristics of the instrumentation
amplifier.

APPARATUS REQUIRED:

1.   Operational Amplifier     IC741 -3No
2.   Resistors                 10K -7No
3.   RPS
4.   Function Generator
5.   CRO

PROCEDURE:
1. Connections are given as per the circuit diagram
2. Input voltage is set at 1V peak to peak in sinusoidal mode
3. Input frequency is varied from 100Hz till the output waveform is not
distorted
4. Corresponding peak to peak magnitude of the output waveform is noted
down
5. Gain is calculated and tabulated
6. Graph is plotted between input frequency and gain in db scale
7. Calculate the corner frequency from the frequency response plot.

RESULT:
Thus the frequency response characteristics of an instrumentation amplifier
has been obtained & plotted
D/A CONVERTER

AIM
To convert the given digital input into its equivalent analog output.

OBJECTIVE
5.    To study the conversion of binary voltage to analog o/p voltage
6.    To study the operation and characteristic of operational amplifier

EQUIPMENT
IC 741                     – 1 No
Resistor     1K           – 2 No
2.2k         – 7 No
100          –1 No
Multimeter                 –1No
Dual Power Supply          (0-30)V       1No
Bredboard & Connecting Wires

CIRCUIT DIAGRAM:
PROCEDURE:

vi.       Make the connections as per the circuit diagram
vii.      Apply the binary input by closing appropriate switches
viii.     Measure the analog output using a multimeter.
ix.       Tabulate the measured values.
x.        Plot a graph between digital input Vs analog output and digital input Vs %
output.

RESULT:

Thus the given digital input is converted into its equivalent analog output.
A/D CONVERTER
AIM

OBJECTIVE
5.     To study the conversion of analog I/P voltage to digital o/p voltage.
6.     To study the operation and characteristic of operational amplifier
COMPONENETS REQUIRED
Op Amp        LM741           -3No
Resistors     470            -3No
1K             -4No
LED                           -3No
RPS           (0-5V)          -1No
CIRCUIT DIAGRAM:
EXERCISE
6.     Verify the practical output with theoretical output

PROCEDURE:
i.     The connections are made as shown in diagram
ii.    The voltage is increased in steps. The analog input is also given
iii.   The truth table is verified

RESULT:

Thus the analog to digital convertor was implemented and the truth table verified
STUDY OF TRANSIENTS

RC TRANSIENTS:
AIM
To Observe and plot the transients waveform for a series RC circuit and compute
the time constant.
OBJECTIVE
7. To study the transient behaviour of the given system
8. To study the effects of transients
COMPONENTS REQUIRED
11. Resistance         – 1 No
12. Capacitance        – 1 No
13. Signal Generator
14. CRO & Probes
15. Bred board & Connecting Wires

NOTE
Choose the frequency (f) in signal generator such that f < (4z)^-1 where Z=RxC

CIRCUIT DIAGRAM:
EXERCISE
5. Draw the response curve for the given system
6. Find the time when the error is minimum

PROCEDURE:
i.      Make the connections as per the circuit diagram
ii.     Choose square wave made in signal generator and apply a suitable
input
iii.    Observe and plot the output waveform
iv.     Calculate the time required by output to reach 0.368 times the
input value(peak)
v.      This value given practical time constant

RESULT:
Thus the transient nature of RC circuit has been studied and the waveform plotted

RL TRANSIENTS:

AIM:
To observe and plot the transient waveform for a series RL circuit and compute
the time constant

OBJECTIVE
9. To study the transient behavior of the given system
10. To study the effects of transients
COMPONENTS REQUIRED
Resistance            1KOhm           – 1 No
Inductor              10mH            – 1 No
Signal Generator
CRO & Probes
Bred board & Connecting Wires

NOTE
Choose the frequency (f) in signal generator such that f < (4z)^-1 where Z=L/R

CIRCUIT DIAGRAM:

PROCEDURE:
vi.         Make the connections as per the circuit diagram
ii. Choose square wave made in signal generator and apply a suitable input
iii. Observe and plot the waveform
iv.      Calculate the time required by output to reach 0.632 times the input
value(peak)
v. This value given practical time constant

RESULT:
Thus the transient nature of RL circuit has been studied and the waveform plotted
MEASUREMENT OF IRON LOSS (MAXWELL BRIDGE)

AIM
To Measure the iron loss of a given ring specimen
OBJECTIVE
5. To study about hysterisis loss
6. To study about eddy current loss
EQUIPMENT:
    Ring Specimen
    Measurement of iron loss trainer
    CRO

CIRCUIT DIAGRAM
PROCEDURE:

9. Patch the circuit as per the circuit diagram
10. Connect the ring specimen to the corresponding connector provided on the front
panel left corner
11. Switch ON the trainer observes the CRO output which should be some value
12. We have to null this output for that adjust the R value by using both fine and
13. Further adjust the L value until the Vout get a null condition.
14. Observe the ammeter value
15. Switch OFF the trainer
16. Measure the R value, L value using multimeter

RESULT:
The iron loss of the given ring specimen was calculated by using Maxwell’s Bridge.
INSTRUMENTATION AMPLIFIER

AIM:
To obtain the frequency response characteristics of the instrumentation amplifier.

APPARATUS REQUIRED:

6. Operational Amplifier IC741 -3No
7. Resistors                       10K -7No
8. RPS
9. Function Generator
10. CRO

CIRCUIT DIAGRAM
PROCEDURE:
8. Connections are given as per the circuit diagram
9. Input voltage is set at 1V peak to peak in sinusoidal mode
10. Input frequency is varied from 100Hz till the output waveform is not distorted
11. Corresponding peak to peak magnitude of the output waveform is noted down
12. Gain is calculated and tabulated
13. Graph is plotted between input frequency and gain in db scale
14. Calculate the corner frequency from the frequency response plot.

RESULT:
Thus the frequency response characteristics of an instrumentation amplifier has
been obtained & plotted
MEASUREMENT OF 3 PHASE POWER AND POWER FACTOR

AIM
To conduct a suitable experiment on a 3-phase load connected in star or delta to
measure the three phase power and power factor using 2 wattmeter method.

OBJECTIVES
5.    To study the working of wattmeter
6.    To accurately measure the 3 phase power
7.    To accurately measure the power factor
8.    To study the concept of star connected load and delta connected load

APPARATUS REQUIRED
1.    3 phase Auto transformer     – 1 No
2.    M.I Ammeter                  – 1 No
3.    M.I Voltmeter                – 1 No
4.    Wattmeter                    – 1 No
CIRCUIT DIAGRAM:
(0-10)A MI
10A
M                L
R                          A

V
C
3 phase
440V,              T                                                    variable
3 AC                                                                    resistive
ssupply
10A
Y                  S

T

440, 3 AC            S
supply
440V,
3 AC
supply                                   C                           V
ssupply                  10A
B

M                L

600V, 10A UPF

TPST- Triple Pole Single throw Switch

MI- Moving Iron

UPF- Unity Power Factor

EXERCISE

3.    Measure the real power, reactive power and power factor of 3 phase resistive
4.        Measure the real power, reactive power and power factor of 3 phase resistive

PROCEDURE:

1.Connection are made as per the circuit diagram, Keeping the inductive load in the
initial position.
2.Supply switch is closed and reading of ammeter and wattmeter are noted .If one of the
wattmeter reads negative, then its potential coils (C and V) are interchanged and

3.The above procedure is repeated for different values of inductive coil. Care should be
taken that current should not exceed 10A during the experiment.

TABULAR COLUMN:

S.NO                 I               W1            W2           POWER          P.F
P
(Amps)          (Watts)        (Watts)        Watts       COS

FORMULA USED:

4. Total power P = W1+W2 (W)
5.  = Tan-1 3[W1-W2/W1+W2]
6. P.F = Cos.

RESULT:
The Power and Power factor of the given coil is measured by using only two
wattmeters.
5.  = Tan-1 3[W1-W2/W1+W2]
6. P.F = Cos.

RESULT:
The Power and Power factor of the given coil is measured by using only two
wattmeters.

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Description: EXPT NO MEASUREMENT OF RESISTANCE USING WHEATSTONE BRIDGE