A 200 V, dc series motor takes 40 A when running at 700 rpm. Calculate the speed at which the motor will run and the current taken from the supply if the field is shunted by a resistance double the field resistance and the load torque is increased by 50%. Armature resistance = 0.15 Ω, field resistance = 0.1 Ω It may be assumed that flux per pole is proportional to the field.

A 200 V, dc series motor takes 40 A when running at 700 rpm. Calculate the speed at which the motor will run and the current taken from the supply if the field is shunted by a resistance double the field resistance and the load torque is increased by 50%. Armature resistance = 0.15 Ω, field resistance = 0.1 Ω It may be assumed that flux per pole is proportional to the field.

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter8: Basic Electric Motors

Section: Chapter Questions

Problem 2RQ

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