Q.1- A d.c. shunt machine has armature and field resistances of 0.025 2and 80 2 respectively. When connected to const 400 V bus-bars and drivenas a generator at 450 r.p.m. it delivers 120 Kw. Calculate its speed whenrunning as a motor and absorbing 120 Kw from the same bus-bar. Also,deduce the direction rotation of this machine when it is working as a motorassuming clockwise rotation as a generator.Ans. 435 r.p.m.Q.2- A 4-pole, 500V, 100 hp, wave connected motor has 492 conductors.The flux per pole is 50 mWb and full-load efficiency is 92%. Its shunt fieldresistance is 250 2 and armature circuit resistance is 0.1 Q, calculate forfull load:a. motor speed.b. the useful torque developed (output torque).Ans. 590 r.p.m. , 1207 N.m

Answered: Image /qna-images/answer/ca5d7795-23e7-4292-8cbe-a097d775a168.jpg

Q.2- A 4-pole, 500V, 100 hp, wave connected motor has 492 conductors. The flux per pole is 50 mWb and full-load efficiency is 92%. Its shunt field resistance is 250 N and armature circuit resistance is 0.1 2, calculate for full load: a. motor speed. b. the useful torque developed (output torque). Ans. 590 r.p.m. , 1207 N.m

Q.2- A 4-pole, 500V, 100 hp, wave connected motor has 492 conductors. The flux per pole is 50 mWb and full-load efficiency is 92%. Its shunt field resistance is 250 N and armature circuit resistance is 0.1 2, calculate for full load: a. motor speed. b. the useful torque developed (output torque). Ans. 590 r.p.m. , 1207 N.m

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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DC generators
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