D8.7 A three-phase, 30-hp, 480-V, four-pole, 60-Hz induction motor has the following equivalent circuit parameters in 2 per phase referred to the stator: R₁ = 0.25 R₂ = 0.20 X₁ = 1.30 X₂ = 1.20 Xm = 35 The total core, friction, and windage losses may be assumed constant at 1250 W. The motor is connected directly to a 440-V source, and it runs at a slip of 3.5%. Compute the following: a. Motor speed b. Input current and power factor c. Shaft output torque d. Efficiency of the motor

D8.7 A three-phase, 30-hp, 480-V, four-pole, 60-Hz induction motor has the following equivalent circuit parameters in 2 per phase referred to the stator: R₁ = 0.25 R₂ = 0.20 X₁ = 1.30 X₂ = 1.20 Xm = 35 The total core, friction, and windage losses may be assumed constant at 1250 W. The motor is connected directly to a 440-V source, and it runs at a slip of 3.5%. Compute the following: a. Motor speed b. Input current and power factor c. Shaft output torque d. Efficiency of 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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