4. e principle of operation of a 3-phase. Induction motor is most similar to that of a (a) synchronous motor (b) DC motor (c) transformer with a shorted secondary (d) SPIM 5. 500 kW, 3-phase, 440 volts, 50 Hz, A.C. induction motor has a speed of 960 r.p.m. on full load. The machine has 6 poles. The slip of the machine will be (a) 0.01 (b) 0.02 (c) 0.03 (d)0.04 6. A centrifugal switch is used to disconnect 'starting winding when motor has (a) picked up about 50 to 75 per cent of rated speed (b) picked up about 10 to 15 per cent of rated speed (c) run for about 1 minute inutes

4. e principle of operation of a 3-phase. Induction motor is most similar to that of a (a) synchronous motor (b) DC motor (c) transformer with a shorted secondary (d) SPIM 5. 500 kW, 3-phase, 440 volts, 50 Hz, A.C. induction motor has a speed of 960 r.p.m. on full load. The machine has 6 poles. The slip of the machine will be (a) 0.01 (b) 0.02 (c) 0.03 (d)0.04 6. A centrifugal switch is used to disconnect 'starting winding when motor has (a) picked up about 50 to 75 per cent of rated speed (b) picked up about 10 to 15 per cent of rated speed (c) run for about 1 minute inutes

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

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