A 480 V, 2-poles, 60 Hz, Y-connected induction motor has an inductive reactance of 4ohm and the resistance of R, = 0.2ohm and R', 0.3ohm. The motor is driving a constant-torque load of 150 Nm at a speed of 3500 rpm. Assume that this torque includes the rotational components. Calculate the motor speed and starting current if the frequency is decreased to 50 Hz.

A 480 V, 2-poles, 60 Hz, Y-connected induction motor has an inductive reactance of 4ohm and the resistance of R, = 0.2ohm and R', 0.3ohm. The motor is driving a constant-torque load of 150 Nm at a speed of 3500 rpm. Assume that this torque includes the rotational components. Calculate the motor speed and starting current if the frequency is decreased to 50 Hz.

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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