A universal motor has a total resistance of 30 and a total inductance of 0.5 H. When connected to a 250 V dc supply and loaded to 0.8 A, it runs at 2000 rpm. Determine (a) the speed in rpm, (b) developed torque, and (c) power factor when connected to 250 V, 50 Hz ac supply and loaded to take same amount of current.

A universal motor has a total resistance of 30 and a total inductance of 0.5 H. When connected to a 250 V dc supply and loaded to 0.8 A, it runs at 2000 rpm. Determine (a) the speed in rpm, (b) developed torque, and (c) power factor when connected to 250 V, 50 Hz ac supply and loaded to take same amount of current.

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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