A 10 kW, 250 V, dc shunt motor with an armature resistance of 0.8 Ω and a field resistance of 275 Ω takes 3.91A, when running light at rated voltage and rated speed. What conclusions can you draw from the above data regarding machine losses? Calculate the machine efficiency as a generator when delivering an output of 10 kW at rated voltage and speed and as a motor drawing an input of 10 kW. What assumption if any do you have to make in this computation?

A 10 kW, 250 V, dc shunt motor with an armature resistance of 0.8 Ω and a field resistance of 275 Ω takes 3.91A, when running light at rated voltage and rated speed. What conclusions can you draw from the above data regarding machine losses? Calculate the machine efficiency as a generator when delivering an output of 10 kW at rated voltage and speed and as a motor drawing an input of 10 kW. What assumption if any do you have to make in this computation?

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter29: Dc Generators

Section: Chapter Questions

Problem 1PA: You are working as an electrician in a large steel manufacturing plant, and you are in the process...

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