156. A small 3-phase induction motor has a short- circuit current 5 times of full-load current and full-load slip 5%. If starting resistance starter is used to reduce the impressed voltage to 60% of normal voltage, the starting torque obtained in terms of full load torque would be

156. A small 3-phase induction motor has a short- circuit current 5 times of full-load current and full-load slip 5%. If starting resistance starter is used to reduce the impressed voltage to 60% of normal voltage, the starting torque obtained in terms of full load torque would be

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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Concept explainers

Single Phase Induction Motor

The single-phase induction motor or engine consists of a single rotating phase in the stator and a rotating cage in the rotor. When phase one supply is connected to the stator winding, a magnetic field is generated. In the pulsating field, the rotor does not rotate due to inertia. So, a single-phase import motor does not start and requires some initial methods.

Question

156. A small 3-phase induction motor has a short-
circuit current 5 times of full-load current and
full-load slip 5%. If starting resistance starter
is used to reduce the impressed voltage to 60%
of normal voltage, the starting torque obtained
in terms of full load torque would be

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