A 415V, 50HZ, 3-phase induction motor supplies its rated power to a b) constant load. The rated speed of the motor is 980 rpm. (i) Identify the pole number of the motor and calculate the rate slip (ii) Draw the circuits for the no-load and block-rotor tests and indicate the slip for each of the tests. (iii) If the supply voltage is changed to 332V and 40HZ, calculate the motor speed, slip frequency, and slip.

A 415V, 50HZ, 3-phase induction motor supplies its rated power to a b) constant load. The rated speed of the motor is 980 rpm. (i) Identify the pole number of the motor and calculate the rate slip (ii) Draw the circuits for the no-load and block-rotor tests and indicate the slip for each of the tests. (iii) If the supply voltage is changed to 332V and 40HZ, calculate the motor speed, slip frequency, and slip.

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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