SHRI VISHNU ENGINEERING COLLEGE FOR WOMEN:: BHIMAVARAM (AUTONOMOUS)

DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING

DC MACHINES LABORATORY

Course Objective: obtain the characteristics of DC motors and generators by performing brake tests and load

tests respectively.

Course Outcomes: CO1:. Able to determine the critical field resistance and critical speed of DC Generator

CO2: To predetermine the efficiency of a given DC Shunt machine working as Motor and

Generator.

CO3: Able to obtain performance characteristics of DC Motors and Generators

CO4: To determine the efficiencies of DC Series and Shunt generators

LIST OF EXPERIMENTS

Any ten of the experiments from the following 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 Load test on DC Series Generator. Determination of Characteristics

4 Load test on DC Compound Generator. Determination of Characteristics

5 Hopkinson’s test on DC Shunts machines. Predetermination of efficiency.

6 Field’s test on DC Series machines. Determination of efficiency.

7 Swinburne’s Test and Predetermination of efficiencies as Generator and Motor

8 Brake Test on DC Compound motor. Determination of performance curves.

9 Brake Test on DC Shunt motor. Determination of Performance curves

10 Separation of losses in DC Shunt motor

11 Speed Control of DC Shunt Motor by Field and Armature control

12 Retardation Test on DC Shunt Machine

List of Equipment with cost

S.NO. NAME OF THE EQUIPMENT QUAN

TITY

COST

1 DC Shunt Motor coupled Shunt Generator with base plate.

Motor: 220V, 5HP, 19A, 1500 RPM.

Generator:220V,3KW,13.5A,1500 RPM, Field regulator for

motor, Field regulator for generator, 3 point Starter

2

50,679.00

2 DC Compound Motor coupled DC Compound Generator with

base plate. Motor: 220V, 9A,1500 RPM, Generator: 220V,

9KW, 1500RPM, Field regulator for motor, Field regulator for

generator, 4 point Starter.

1

37,530.00

3 DC Compound Motor coupled DC Series Generator with base

plate, Motor: 220V, 9A, 1500 RPM, Generator:220V, 2KW,

1500RPM, Field regulator for motor, Field regulator for

generator, 4 point Starter

1

38,197.00

4 DC Series Motor coupled DC Series Generator with base plate,

Motor: 220V,9A,1500RPM, Field regulator for motor, Field

regulator for generator,2 point Starter 1

40,750.00

5 DC Shunt Motor coupled Shunt Generator with base

plate,Motor:220V,1500RPM, Generator:220V,2KW,1500RPM,

Field regulator for motor, Field regulator for generator, 3 point

Starter

1

38,840.00

6 DC Shunt Motor 3HP, 220V, 1500RPM with brake drum

arrangement, Field regulator, 3-point Starter. 3

1,47,453.00

7 DC Compound Motor 3 HP,220 V,1500 RPM with brake drum

arrangement, Field regulator, 4-point Starter 1 24,653.00

8 DC Series Motor 3 HP, 220 V, 12 A, 1500 RPM with brake

drum arrangement, Field regulator, 2-point Starter 1 26,800.00

9 DC shunt Motor-Shunt Generator panel board with indicating

lamps (2.6W,250V) 3 pole MCB, fuses (15A) 3-No. Rectifier

from 3 phase, Variable RPM meter (0-2000) RPM, Ammeter

(0-2A MC), (0-20A MC)

2

52,000.00

10 DC Compound Motor-Compound Generator panel board with

indicating lamps (2.6W, 250V), 3 pole MCB. Fuses(15A)3-No.,

Rectifier from 3-phase, Variable RPM meter (0-2000) RPM.

Ammeter (0-20A) MC, (0-2A) MC

Volt meter (0-300V) MC , (0-30V) MC

Field rheostat for motor 200Ω/2A

1

25,500.00

11 DC Compound Motor-Series Generator panel board with

indicating lamps (2.6W, 250V) 3 pole 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

1

25,500.00

12 DC Series Motor-Series Generator panel board with 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

1

30,000.00

13 DC Shunt Motor-Shunt Generator panel board with 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

1

30,000.00

14 DC Shunt Motor panel board, 3-point starter, indicating lamps

(2.6W,250V), 2poleMCB, Fuses (15A)3-No., RPM meter (0-

2000)RPM, Ammeter(0-20A)MC, (0-2A)MC, Voltmeter(0-

300V)MC, (0-30V)MC

2

28,000.00

15 DC Shunt Motor panel board with 3-point starter, indicating

lamps (2.6W, 250V), 2 pole MCB, Fuses (15A) 3-No., RPM

meter (0-2000)RPM, Ammeter (0-20A)MC, (0-2A)MC,

Voltmeter (0-300V)MC,(0-30V)MC

1

26,000.00

16 DC Compound Motor panel board with 4 point starter and Field

regulator, indicating lamps(2.6W,250V) 2 poles MCB, Fuses

(15A) 20No. RPM meter (0-2000) RPM, Ammeter(0-20A)

MC, (0-2A) MC, Voltmeter (0-300V)MC

1

14,000.00

17 DC Machines Lab control panel with indicating lamps 4No.,

Ammeter (MC) (0-100A), (MI) (0-100A), Voltmeter (MI) (0-

500V) (MI)(0-300V). Frequency meter (45-55) Hz, selector

switch-2-No. S.F.U-2-No., 3 pole MCB 15-No., 2 poles MCB

15-No.

1

14,000.00

18 DC voltmeter (0-300V) 6 6,210.00

19 DC voltmeter (0-50V) 10 10,800.00

20 DC voltmeter (0-75/150V ) 12 12,600.00

21 DC voltmeter (0-75/150/300/600V) (MC) 23 23,805.00

22 Knife switches

SPST

DPDT

SPDT

TPDT

TPST

10

10

5

5

3

3,400.00

8,710.00

2,165.00

6,545.00

3,111.00

Total 7,27,248.00

AC MACHINES LAB

Course Objective:

performance.

conduct No–load & Blocked rotor tests and Brake test on three phase Induction motor

–phase alternator by synchronous impedance method

—phase synchronous machine

Course Outcomes:

CO1: Able to predetermine the efficiency and regulation of single-phase transformer at given

power factors and determine its equivalent circuit.

CO2: Able to obtain performance characteristics three-phase Induction motor

CO3: To predetermine the regulation of three–phase alternator by synchronous impedance

method

CO4:To determine Xd and Xq of a salient pole synchronous machine

CO5: Able to obtain the V and Inverted V curves of a three—phase synchronous motor

SYLLABUS

The following experiments are required to be conducted as compulsory experiments:

1. O.C. & S.C. Tests on Single phase Transformer

2. Sumpner’s test on single phase transformers

3. Scott connection of transformers

4. No–load & Blocked rotor tests on three phase Induction motor

5. Regulation of a three –phase alternator by synchronous impedance &m.m.f. Methods

6. V and Inverted V curves of a three—phase synchronous motor.

7. Equivalent Circuit of a single phase induction motor

8. Determination of Xd and Xq of a salient pole synchronous machine

In addition to the above eight experiments, at least any two of the following experiments

are required to be conducted from the following list:

1. Parallel operation of Single phase Transformers

2. Separation of core losses of a single phase transformer

3. Brake test on three phase Induction Motor

4. Regulation of three–phase alternator by Potier triangle method.

5. Efficiency of a three–phase alternator

6. Heat run test on a bank of 3 Nos. of single phase Delta connected transformers

7. Measurement of sequence impedance of a three–phase alternator.

List of Equipment with cost

S.NO . NAME OF THE EQUIPMENT QUANTITY COST

1 3-phase Induction Motor squirrel cage type, with

brake drum arrangement, star delta starters, A.C,

440V, 50Hz 5 H.P, 8A, 1400 r.p.m.(p) ltd. MAKE:

BENN ELECTRICALS

1

23,012.50

2 3-phase Induction Motor slip ring type, with brake

drum arrangement, Rotor resistance starter. A.C,

440V, 50Hz, 5 H.P, 8A, 1400 r.p.m. MAKE: BENN

ELECTRICALS (p) ltd.

1

39,296.30

3 DC Shunt Motor coupled to Alternator with base

plate, Motor: DC, 220V, 5HP, 18A, 1500 r.p.m.

Alternator: 3KVA, 400V, 8A, 1500 r.p.m, Field

regulator for motor & 3-point starter, static

excitation unit. MAKE: BENN ELECTRICALS(P)

LTD.

1

55,557.20

4 DC Shunt Motor coupled to Alternator with base

plate, Field regulator for motor, 3-point starter, static

excitation unit AC 3Φ, 400V, 50Hz, 8A, 1500 rpm 1

56,580.00

5 Synchronous Motor, 3 H.P, 415V, 3Φ, 50Hz, 1500

r.p.m, Synchronous motor frame (rotor wound stator

excited) suitable for DOL starter with 4 wires

mechanical loading, excitation unit.

1

40,680.00

6 1Φ, Induction Motor with brake drum, spring

balances, 1H.P, 1Φ, 230V, 1440r.p.m. 50Hz, AC,

Induction Motor capacitor start & run motor

1

16,190.00

7 Pole-changing Inductor Motor with drum

arrangement AC-3Φ, 50Hz, 450V, 1.5 KW. 1

19,930.00

8 DC Compound Motor coupled to a 3Φ Induction

Motor, AC, 50Hz, 415V, 5 H.P, 1500 r.p.m. 1

30,740.00

9 3-Φ squirrel cage Induction Motor panel board with

Y/∆ starter. Indicating lamps-3. 3 pole M.C.B (16A,

600V)-1No. Fuses(10A)-3No., R.P.M. meter (0-

2000 rpm) Ammeters (0-10A) MI-1No., Voltmeter

(0-500V) MI-1No., Waltmeter 600V/10A-2No.

separates terminals for each component

1

23,000.00

10 Shunt Motor coupled to Alternator panel board with

indicating lamp-1, 3 pole M.C.B. -16A, 600V-1

Fuses(10A)-3, R.P.M. meter (0-2000 rpm) Ammeter

(0-20A(MI)-1, Voltmeter 0-500V(MI)-1,

Wattmeters 600V/10A-2,Field rheostats for motor-1,

Separate terminals for each component.

1

25,000.00

11 Salient pole Alternator panel board with indicating

lamp-1No., Fuses-3 No., MCB-1No., Ammeter-20A,

Voltmeter -500V, Ammeter-2A , DC RPM meter

separate terminal for each component

1

32,000.00

12 Transformer indicating lamps-1, 3-pole MCB-16A,

600V-1, Fuses-10A-2, Ammeters(MI) (0-10A)-1 , (0-

5A)-1, Voltmeters (MI) (0-300V)-1, Wattmeters

(300V/2.5A)-1, (75V/5A)-1, Separate terminals for

each component

1

23,000.00

13 Scott connected Transformer indicating lamp (2.6W,

250V, AC/DC):-1 No.

1

23,000.00

14 Synchronous motor indicating lamp (26W,250V

AC/DC) 3No., 3 pole MCB (415V, 20A,50Hz) 1No.

Fuses (10A)-3 No., RPM meters (0-2000 rpm) -1,

Ammeters(0-15A) MI-1, (0-5A) MI- 1 , Voltmeters (0-

300V) MI -1, Frequency meter (45-55HZ) -1,

Wattmeters (300V/5A)- 1, Field rheostat (600Ω/2A)- 1,

Separate terminals for each component

1

22,000.00

15 Changing I.M. indicating lamps -3No., 3 pole MCB-

1No., RPM meter -1No.(0-2000), Ammeters (0-10A)

MI -1, Voltmeters (0-500V) MI-1, Wattmeters

(600V/10A) -2, Separate terminals for each component

--

12,000.00

16 DC Machines control panel with indicating lamps-4

ammeters (mc) (0-100A)-1 (MI) (0-100A)-1 voltmeters

(MI) (0-500V)-1 (MC) (0-300V)-1 frequency meters

(45-55Hz)-1 selector switches-2 S.F.U-2, 3 pole MCB-

15, 2 pole MCB-15, CT-1 set, PT-1 set, Busbar-1

1

32,000.00

17 A.C. Machine control panel indicating lamps-3

Ammeters (MI) (0-100A)-1, Voltmeter (MI) (0-500V)-

1, Frequency meters (45-55Hz)-1, Selector switches-2

S.F.U-1, 3 pole MCB-12 ,CT-1 set, PT-1 set, Bus bar-1

1

32,000.00

18 Ammeters -A.C 0-20A 2 2000 .00

0-10A 4 4000.00

0-5A 3 3000.00

0-2A 4 4000.00

19 0-1A 2 2,270.00

20 Ammeter (0-2.5/5/10A) 12 12,420.00

21 Voltmeter (0-300V) 1 1,000.00

22 Voltmeter (0-600V) 3 3,000.00

23 Voltmeter (0-50V) 2 2,000.00

24 Voltmeter (0-250V) 3 3,240.00

25 Voltmeter (0-50V) 1 1,015.00

26 Voltmeter (0-75/150/300/600V) 14 14,490.00

27 Wattmeter (75V/5A ) 2 3,300.00

28 Wattmeter (75/150V,10A ) 3 5,197.50

29 Wattmeter (600V,10A) 2 6,900.00

30 Wattmeter (600V,20A) 1 3,450.00

31 Wattmeter (75V/15A/300V/5/10A ) 6 11,340.00

32 Wattmeter (150/300/600V, 5/10A) 6 21,384.00

33 Wattmeter(75/150/300,2.5/5A) 5 19,775.00

34 P.F meter (5/10A, 100/300/600V) 1 2,756.00

35 1-Φ Auto transformer 15A, 0-270V 1 3,588.00

36 3-Φ auto transformer 15A, 0-470V 2 20,080.00

37 1-Φ auto transformer 15A, 230V/0-270V 1 3,588.00

38 1-Φ auto transformer 8A, 230V/0-270V 2 4,202.00

39 1-Φ auto transformer 10A, 230V/0-270V 1 2,467.00

40 3-Φ auto transformer 15A, 0-470V 1 12,337.00

41 Transformer 1-Φ 230V/115V, 2KVA 2 12,824.40

42 Transformer 1-Φ 230V/115V, 1KVA 2 7,529.80

43 Transformer 1-Φ 230V/115V, 2KVA 2 16,400.00

44 Scott transformer with scott tapping at 50% & 89.69%

on HV side 3.5% regulation 1 KVA 230V/115V 2 9,800.00

45 Transformer 1KVA 230V/115V 1 5,500.00

46 STEP down transformer 1-Φ , 2 K.V.A 2 13,000.00

47 Digital tachometers 3 5,940.00

48 Frequency meter indication read type 1 1,741.00

49 Frequency meter vibrating type read type 1 1,741.00

50 Synchroscope 1 3,753.00

51 Phase sequence meter 1 523.00

Total 757537.00