ELECTRICAL MACHINES LAB – I
Objective: This Lab explores all the possible design connections of a DC machine and it also
experimentally obtains the characteristics and thus observes the performance of different DC motors and
generators and performs tests on DC machines to derive their efficiency.
Outcomes: At the completion of this lab, the student will be able to:
1. Obtain the operating characteristics of dc machines.
2. Examine the relationship between torque, speed, voltage and current for various types of motor
connections in no-load and loaded configurations.
3. Predict, by calculation, the performance of dc machines.
4. Analyze and select appropriate dc machines for given applications.
List of Experiments:
Any 10 of the following experiments are to be conducted:
1. Magnetization characteristics of DC shunt generator. Determination of critical field resistance and
critical speed.
2. Load test on DC shunt generator. Determination of characteristics.
3. Brake test on DC shunt motor. Determination of performance curves.
4. Load test on DC compound generator. Determination of characteristics.
5. Hopkinson’s test on DC shunt machines. Predetermination of efficiency.
6. Fields test on DC series machines. Determination of efficiency.
7. Swinburne’s test and speed control of DC shunt motor. Predetermination of efficiencies.
8. Speed control of DC shunt motor by field and armature control.
9. Brake test on DC compound motor. Determination of performance curves.
10. Load test on DC series generator. Determination of characteristics.
11. Retardation test on DC shunt motor. Determination of losses at rated speed.
Additional Experiments :
12. Separation of losses in DC shunt motor.
13. Simulation of separately excited DC machine using MATLAB/Simulink.
List of Equipment with cost:
S.NO
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13.
NAME OF THE EQUIPMENT
DC shunt coupled shunt generator, DC shunt motor coupled
shunt generator with base plate and coupled.
DC shunt motor: 220V, 5HP, 19A,1500r.p.m.
DC shunt generator:220V,3KW,13.5A,1500RPN
Field regulator for motor, field regulator for generator, 4
points starter
DC compound motor coupled DC compound generator with
base plate and coupling motor: 220V, 9A,15000 RPM
generator: 220V, 9KW, 15000RPM field regulators for
motor, field regulator for generator 4 points starter.
DC compound motor coupled. DC series generator with base
plats and coupling motor: 220V, 9A, 15000 RPM
generator:220V,2KW, 1500RPM field regulator for motor,
field regulator for generator, 4 points starter
DC series motor coupled DC series generator with base plats
and coupling motor: 220V,9A,15000RPM field regulator for
motor, field regulator for generator 4 points starter
DC shunt motor coupled shunt generator with base plate and
coupling motor: 220V,1500RPM.
Generator:220V,2KW,1500RPM
DC shunt motor 3HP, 220V, 1500RPM with brake drum
arrangement field regulator 3-points starter.
DC shunt motor 3HP,220V,1500 RPM with brake drum
arrangement field regulator 3-points starter
DC compound motor 3 HP,220 V,1500 RPM with brake
drum arrangement field regulator 4-point starter
DC series motor 3 HP, 220 V, 12 A, 1500 RPM
DC shunt motor shunt generator panel board including lamps
(2.6W,250V) 3 poles MCB, fuses(15A) 3-NO register from 3
phase variable RPM meter 0-2000 RPM
Ammeter (0-2A MC), (0-20A MC)
DC compound motor-compound generator panel board
indicating lamps (2.6W,250V), 3 poles MCB. Fuses (15A) 3No rectifier from 3-phase variable RPM meter 0-2000 RPM.
Ammeter( 0-20AMC), (0-2AMC)
Volt meter (0-300 VMC) , (0-30 VMC)
Field rheostat for motor 200Ω/2A
DC compound motor-series generator panel indicating lamps
(2-6W,250V) 3 poles MCB, Fuses (15A) 3-NO.Rectifier
from 3 phase variable RPM meter 0-2000 RPM. Ammeter ->0-20A MC Voltmeter 0-300V MC field rheostat for motor
200Ω/2A
DC series motor series generator panel board indicating
lamps(2-6W,250V) 3 poles MCB, Fuses(15A) 3-No,Rectifier
QUANTITY
2
COST
50,679.00
1
37,530.00
1
38,197.00
1
40,750.00
1
38,840.00
2
49,151.00
1
21,578.00
1
24,653.00
1
2
26,800.00
52,000.00
1
25,500.00
1
25,500.00
11
30,000.00
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
from 3-phase, Variable RPM meter, 0-2000 RPM, Ammeter
0-20AMC, Voltmeter 0-300VMC, field rheostat for motor
200Ω/2A
DC shunt motor-shunt generator panel board indicating lamps
(2-6W, 250V) 3 poles MCB
Fuses(15A) 3-No rectifier from 3-phase variable RPM meter
0-2000 RPM.Ammeter0-2AMC,0-20AMC, Voltmeter 0300VMC,0-30VMC. Filed rheostat for motor 250Ω/2A,
150Ω/2A
DC shunt motor panel board, 3-pt starter indicating lamps (26W,250V), poles MCB fuses (15A)3-No RPM meter 02000RPM, Ammeter0-20AMC,0-2AMC,Voltmeter0300VMC,0-30VMC
DC shunt motor with starter indicating lamps (2-6W,250V), 2
poles MCB fuses (15A) 3-NO RPM meter 0-2000RPM
Ammeter0-20AMC,0-2AMC,Voltmeter0-300VMC,030VMC
DC compound motor panel board with 4 points starter and
fields regulator indicating lamps(2-6W,250V) 2 poles MCB
fuses (15A) 20no. RPM meter 0-2000 RPM, Ammeter-0-20
AMC,0-2AMC, Voltmeter:0-300VMC
DC machines lab control panel indicating lamps-4-no.
Ammeter(MC) 0-100A, (MI) 0-100A, Voltmeter(MI) 0500V(MI)0-300V. Frequency meter 45-55HZ selector
switch-2-no
S.F.U-2-no, 3 pole MCB 15-no, 2 poles MCB 15-no
DC voltmeter 0-300V
DC voltmeter 0-50V
DC voltmeter 0-75/150V
DC voltmeter 0-75/150/300/600V (MC)
DC voltmeter (75/150/300/600V)
Knife switches
SPST
DPDT
SPDT
TPDT
TPST
Total
Lab Projects:
1. Intelligent/ automatic speed control of DC motor.
2. Automatic Torque control of DC motor.
1
30,000.00
--
14,000.00
2
28,000.00
1
26,000.00
1
14,000.00
1
14,000.00
6
4
2
11
3
3,105.00
4,320.00
2,100.00
11,385.00
3,105.00
10
10
5
5
3
3,400.00
8,710.00
2,165.00
6,545.00
3,111.00
6,35,124.00