A 250 V dc shunt motor takes a current of 30A on a certain load. R= 12 and Rh= 125 Q. Find the resistance to be inserted in series with the armature to reduce the speed to 60% of its original value if the load torque is constant.

A 250 V dc shunt motor takes a current of 30A on a certain load. R= 12 and Rh= 125 Q. Find the resistance to be inserted in series with the armature to reduce the speed to 60% of its original value if the load torque is constant.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 13RQ: A squirrel-cage induction motor is operating at 1175 RPM and producing a torque of 22 Ib-ft. What is...

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Concept explainers

Three Phase Induction Motor

The induction motor is an electric motor that runs on AC (alternating current) and it is of two type single phase motor that work on single-phase power supply and three-phase motor that work on three-phase power supply.

Question

A 250 V de shunt motor takes a current of 30A on a certain load. R= 12 and Rsh=
125 Q. Find the resistance to be inserted in series with the armature to reduce the
speed to 60% of its original value if the load torque is constant.

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