A dc shunt motor runs at 600 rpm on a 240V supply while drawing a line current of 30 A. Its armature and field resistances are 0.5 ohm and 120 ohms respectively. What is the resistance should be placed in series with the armature circuit in order to reduce the speed to 400 rpm. Assume no changes in the armature or field current

A dc shunt motor runs at 600 rpm on a 240V supply while drawing a line current of 30 A. Its armature and field resistances are 0.5 ohm and 120 ohms respectively. What is the resistance should be placed in series with the armature circuit in order to reduce the speed to 400 rpm. Assume no changes in the armature or field current

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter30: Dc Motors

Section: Chapter Questions

Problem 4RQ

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