A 240 V, 4 -pole shunt motor has an armature resistance Of 0.42 and a field resistance of 2402. When driving at 700 r.p.m. aload, the torque of which is proportional to the speed, the armature current is 20A. It is desired to rise the speed from 700 to 900 r.p.m., what resistance must be inserted in the shunt field circuit, assuming the magnetization curve to be a straight line?

A 240 V, 4 -pole shunt motor has an armature resistance Of 0.42 and a field resistance of 2402. When driving at 700 r.p.m. aload, the torque of which is proportional to the speed, the armature current is 20A. It is desired to rise the speed from 700 to 900 r.p.m., what resistance must be inserted in the shunt field circuit, assuming the magnetization curve to be a straight line?

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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