A 220-V shunt motor draws 10 A at 1800 rpm. The armature-circuit resistance is 0.2 Ωand the field-winding resistance is 440 Ω. The rotational loss is 180 W. Determine(a) the back emf, (218.1 V)(b) the driving torque, (10.99 Nm)(c) the shaft torque, and (10.03 Nm)(d) the efficiency of the motor. (85.9%) If the torque developed by the above motor is 20 N-m, determine its(a) speed, (1789.587 rpm)(b) line current, and (17.78 A)(c) efficiency. (91%)Assume that the armature reaction is zero and the rotational loss is proportional to the speed.

A 220-V shunt motor draws 10 A at 1800 rpm. The armature-circuit resistance is 0.2 Ωand the field-winding resistance is 440 Ω. The rotational loss is 180 W. Determine(a) the back emf, (218.1 V)(b) the driving torque, (10.99 Nm)(c) the shaft torque, and (10.03 Nm)(d) the efficiency of the motor. (85.9%) If the torque developed by the above motor is 20 N-m, determine its(a) speed, (1789.587 rpm)(b) line current, and (17.78 A)(c) efficiency. (91%)Assume that the armature reaction is zero and the rotational loss is proportional to the speed.

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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