DC series motor has an armature resistance of 0.060 and a series field resistance of 0.080. The motor is connected to a 400 V supply. The line current is 20 A when the speed of the machine is 1100 rpm. When the line current is 50 A and the excitation (i.e: flux) is increased to 30%, what is the speed of the machine in rpm.

DC series motor has an armature resistance of 0.060 and a series field resistance of 0.080. The motor is connected to a 400 V supply. The line current is 20 A when the speed of the machine is 1100 rpm. When the line current is 50 A and the excitation (i.e: flux) is increased to 30%, what is the speed of the machine in rpm.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter5: Resistors

Section: Chapter Questions

Problem 1PA

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