240-V, 50 Hz, 2pole, 4HP three phase Induction Motor is drawing 10A at 0.9 PF lagging runs at a speed of 251 rad/sec. The stator copper losses are 250W, the core losses are 150 W, and the rotor copper losses are 2% of the power entering the rotor. Friction and windage losses are not neglected. Calculate the following. a. Efficiency of the rotor. b. Efficiency of the motor. c. Mechanical efficiency.

240-V, 50 Hz, 2pole, 4HP three phase Induction Motor is drawing 10A at 0.9 PF lagging runs at a speed of 251 rad/sec. The stator copper losses are 250W, the core losses are 150 W, and the rotor copper losses are 2% of the power entering the rotor. Friction and windage losses are not neglected. Calculate the following. a. Efficiency of the rotor. b. Efficiency of the motor. c. Mechanical efficiency.

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 13RQ: A squirrel-cage induction motor is operating at 1175 RPM and producing a torque of 22 Ib-ft. What is...

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