A Y-Y connected 105 Hp, 3-phase 60 Hz, 4-pole, 270 V squirrel cage induction motor has a rotor speed of 1,600 rpm and a rotor resistance per phase of 0.15 ohm and a blocked rotor reactance per phase of 0.6 ohm. The stator copper and core losses amount to 8% of the total rated output of the motor. a. Determine the over-all efficiency of the machine. b. Calculate the speed at which the maximum torque will be developed by the motor.

A Y-Y connected 105 Hp, 3-phase 60 Hz, 4-pole, 270 V squirrel cage induction motor has a rotor speed of 1,600 rpm and a rotor resistance per phase of 0.15 ohm and a blocked rotor reactance per phase of 0.6 ohm. The stator copper and core losses amount to 8% of the total rated output of the motor. a. Determine the over-all efficiency of the machine. b. Calculate the speed at which the maximum torque will be developed by the motor.

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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