A DC series motor rotates at 1200 rpm and draws 40 A at 240 V. The armature and field resistances are 0.25 Ω and 0.12 Ω, respectively. The iron and friction losses are 0.45 kW. Analyse this motor in the following ways 4.7.2 Determine the developed torque. [Ans: 71.683 Nm] 4.7.3 Calculate the efficiency of the motor. [Ans: 89.146]

A DC series motor rotates at 1200 rpm and draws 40 A at 240 V. The armature and field resistances are 0.25 Ω and 0.12 Ω, respectively. The iron and friction losses are 0.45 kW. Analyse this motor in the following ways 4.7.2 Determine the developed torque. [Ans: 71.683 Nm] 4.7.3 Calculate the efficiency of the motor. [Ans: 89.146]

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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