A 7.40 kW, 240-V shunt motor takes a line current of 4 A when running light. Calculate the efficiency as a motor when delivering full load output, if the armature and field resistance are 0.5 Q and 240 2 respectively. At what output power will the efficiency be maximum? Is it possible to obtain this output from the machine?

A 7.40 kW, 240-V shunt motor takes a line current of 4 A when running light. Calculate the efficiency as a motor when delivering full load output, if the armature and field resistance are 0.5 Q and 240 2 respectively. At what output power will the efficiency be maximum? Is it possible to obtain this output from the machine?

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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