A 220-volt DC series motor is running at a speed of 800 r.p.m and draws 100 A. Total resistance of the armature and field is 0.1 ohm. 1. Calculate the speed when the torque is halved if the magnetic circuit is unsaturated. 2. If the torque was 250 N-m, calculate its new value when the current is doubled and the saturation is occurred

A 220-volt DC series motor is running at a speed of 800 r.p.m and draws 100 A. Total resistance of the armature and field is 0.1 ohm. 1. Calculate the speed when the torque is halved if the magnetic circuit is unsaturated. 2. If the torque was 250 N-m, calculate its new value when the current is doubled and the saturation is occurred

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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