Q.18 A 250 V, 50 hp, 1000 rpm d.c. shunt motor drives a load that requires a constant torque regardless of the speed of operation. The armature circuit resistance is 0.04 2. When this motor delivers rated power, the armature current is 160 A. If the flux is reduced to 70% of its original value, find the new value of the armature current.

Q.18 A 250 V, 50 hp, 1000 rpm d.c. shunt motor drives a load that requires a constant torque regardless of the speed of operation. The armature circuit resistance is 0.04 2. When this motor delivers rated power, the armature current is 160 A. If the flux is reduced to 70% of its original value, find the new value of the armature current.

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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