Single Phase Induction Motors - Interview Questions | Exam2Win

Take a timed mock test specifically for Single Phase Induction Motors.

16. If the capacitor of a single-phase motor is short-circuited

A. the motor will not start

B. the motor will run

C. the motor will run in reverse direction

D. the motor will run in the same direction at reduced r.p.m.

Explanation:

17. The power factor of a single-phase induction motor is usually

A. lagging

B. always leading

C. unity

D. unity to 0.8 leading

Explanation:

18. In a shaded pole motor, the shading coil usually consist of

A. a single turn of heavy wire which is in parallel with running winding

B. a single turn of heavy copper wire which is short-circuited and carries only induced current

C. a multilayer fine gauge copper wire in parallel with running winding

D. none of the above

Explanation:

19. The running winding of a single phase motor on testing with meggar is found to be ground. Most probable location of the ground will be

A. at the end connections

B. at the end terminals

C. anywhere on the winding inside a slot

D. at the slot edge where coil enters or comes out of the slot

Explanation:

20. A centrifugal switch is used to dis- connect 'starting winding when motor has

A. run for about 1 minute

B. run for about 5 minutes

C. picked up about 50 to 70 per cent of rated speed

D. picked up about 10 to 25 per cent of rated speed

Explanation: