We consider a parallel - excitation DC motor, rated at: 4kW, 1200rpm, 400V. The drum resistance is 10hm and the excitation resistance is 200 Ohm. The motor works with a nominal load torque of 800 rpm, while its voltage is half of the nominal and absorbs 3.8 kW. The mechanical losses are 200 W. Answer the following: a) Calculate the electromagnetic power of the motor. b) Calculate the efficiency of the engine.

We consider a parallel - excitation DC motor, rated at: 4kW, 1200rpm, 400V. The drum resistance is 10hm and the excitation resistance is 200 Ohm. The motor works with a nominal load torque of 800 rpm, while its voltage is half of the nominal and absorbs 3.8 kW. The mechanical losses are 200 W. Answer the following: a) Calculate the electromagnetic power of the motor. b) Calculate the efficiency of the engine.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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