A 120 HP 4-pole 60 Hz induction machine has a friction and windage torque of 18 N-m. The stator-losses are equal the rotor circuit loss. Calculate: (i) The synchronous speed and slip when running at 1200 rpm. (ii) The input power to the stator when delivering full-load output at a speed of 126 rad/s.

A 120 HP 4-pole 60 Hz induction machine has a friction and windage torque of 18 N-m. The stator-losses are equal the rotor circuit loss. Calculate: (i) The synchronous speed and slip when running at 1200 rpm. (ii) The input power to the stator when delivering full-load output at a speed of 126 rad/s.

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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