Question 2) A series DC motor of 250 V. 10 HP has field resistance equal to 0.1 ohms and armature resistance equal to 0.2 ohms. It operates under nominal conditions absorbing from the network a current of 30 A and running at a speed of 1800 rpm. If the applied voltage is reduced to 175 V, what will be the new speed of rotation of the motor (in rpm) if the mechanical torque of the load remains unchanged?

Question 2) A series DC motor of 250 V. 10 HP has field resistance equal to 0.1 ohms and armature resistance equal to 0.2 ohms. It operates under nominal conditions absorbing from the network a current of 30 A and running at a speed of 1800 rpm. If the applied voltage is reduced to 175 V, what will be the new speed of rotation of the motor (in rpm) if the mechanical torque of the load remains unchanged?

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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