New York, NY IMG HI 58° LO 56° Home About Contact
IMG-LOGO
LOGO
Home Electrical and Electronics Electrical Machines 2 To Perform Load Test on 3 Phase AC Slipring Induction Motor.
Electrical Machines 2 Lab Experiments

To Perform Load Test on 3 Phase AC Slipring Induction Motor.

Sep 24 2023


Aim

To Perform Load Test on 3 Phase AC Slipring Induction Motor.

Apparatus Required:

S.no Equipment Type Range Quantity
1 Ammeter MI (0-10)A 1nos
2 Voltmeter MI (0-500)V 10A/600V UPF 1nos
3 Wattmeter Electro dynamo meter type 10A/600V UPF 1no
4 Techometer Digital (0-1000)RPM 1nos
5 Connecting Wires -- (0-20)A Required

Name plate details:-

Power rating : 5Hp

Voltage : 400V

Current : 6.8A

Speed (RPM) : 1500

Frequency : 50Hz

PF : Lagging

Stator : Delta connection

Rotor : Star connection

Circuit Diagram:

circuit-diagram

Procedure:-

  1. Connect circuit. as shown in diagram.
  2. Adjust ‘Zero set’ for Balances.
  3. Switch on Mains supply s/w.
  4. To Start AC Motor, press START Push Button & Shift position of Rotor resistance s/w from 1 to 2 to 3 to 4. Resistance is cut out and rotor is short circuited at position – 4.
  5. Note down readings of voltmeter, Ammeter, Wattmeter’s & load on balances W1 & W2 Kg
  6. Using hand wheel of Brake drum arrangement load the motor in steps from no load to rated torque
  7. Rated torque T = (W1-W2) *A
  8. A = Break drum Constant = Radius of Pulley (Meter) * 9.81
  9. At each step repeat Step 5.
  10. Calculate power output P = 2ЛNT/60.
  11. Calculate efficiency = output / input.

Observation Table:

S.no Voltage VL Line Amps.IL Wattmeter Meters Watts/P1+/P2 I/P Poqwer P1+ P2(W) Load W1Kg Load W2Kg Load W1Kg - Load W2Kg Speed RPM Torque (Nm) Output Power %η
1 420 3.8 0.24/0.29 0.53 0 0 0 1472 0 0 0
2 420 4 0.32/0.19 0.51 4 0.5 3.5 1420 4.12 612.6 30.02
3 420 4.2 0.34/0.09 0.43 4.5 1 3.5 1360 4.12 586.7 34.11
4 420 4.4 0.38/0.04 0.42 6 1.5 4.5 1348 5.29 746.7 44.9

graph
graph-1

Result:Load test is performed on 3-ϴ A.C. Slip ring Induction motor, and characteristics performances are observed.









Related Categories


Laboratory Experiment Categories

Subscribe

Get all latest content delivered to your email a few times a month.