Q-1. 0.75 h.p., 110 V, single-phase induction motor (split-phase) takes a current of 6 Alagging the supply voltage by 25° for the starting winding and a current of 8 A lagging thevoltage by 50° for its main winding, and then A capacitor is added to the starting winding ofthe motor which causes the starting winding current to lead the supply voltage by 34º. Themagnitude of currents in both the starting winding and the main winding remains the same,Calculate (1) the total starting current and the power factor before and after adding capacitor(2) starting torque and the phase angle between the main and starting winding current beforeand after adding capacitor.

Answered: Image /qna-images/answer/c1fde25c-6dd1-4390-a876-4c9a5fbaa519.jpg

Q-1. 0.75 h.p., 110 V, single-phase induction motor (split-phase) takes a current of 6 A lagging the supply voltage by 25° for the starting winding and a current of 8 A lagging the voltage by 50° for its main winding, and then A capacitor is added to the starting winding of the motor which causes the starting winding current to lead the supply voltage by 34°. The magnitude of currents in both the starting winding and the main winding remains the same, Calculate (1) the total starting current and the power factor before and after adding capacitor (2) starting torque and the phase angle between the main and starting winding current before and after adding capacitor.

Q-1. 0.75 h.p., 110 V, single-phase induction motor (split-phase) takes a current of 6 A lagging the supply voltage by 25° for the starting winding and a current of 8 A lagging the voltage by 50° for its main winding, and then A capacitor is added to the starting winding of the motor which causes the starting winding current to lead the supply voltage by 34°. The magnitude of currents in both the starting winding and the main winding remains the same, Calculate (1) the total starting current and the power factor before and after adding capacitor (2) starting torque and the phase angle between the main and starting winding current before and after adding capacitor.

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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