A DC series motor, running a fan at 1000 rpm, take 50 A from 250 V mains. The armature plus field resistance is 0.6 Q. If an additional resistance of 4.4 Q is inserted in series with the armature circuit, the motor speed (approximately) in case the field flux is proportional to armature current is rpm.

A DC series motor, running a fan at 1000 rpm, take 50 A from 250 V mains. The armature plus field resistance is 0.6 Q. If an additional resistance of 4.4 Q is inserted in series with the armature circuit, the motor speed (approximately) in case the field flux is proportional to armature current is rpm.

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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