Problems A 25-hp 240-V 77.8-A shunt motor has an armature resistance of 0.083 N and a field-circuit resistance of 125 1. Calculate the copper losses when the motor is opereting at rated conditions. If the half-load armature current of the motor in Prob. 11.1 is 40 A, determine all copper losses. The field-circuit resistance and armature-circuit resistance of a 10- hp 115-V motor are 90 2 and 0.08 I1, respinctively. Determine the electrical power converted to mechanital power whan the motor draws SK) A from the line.

Problems A 25-hp 240-V 77.8-A shunt motor has an armature resistance of 0.083 N and a field-circuit resistance of 125 1. Calculate the copper losses when the motor is opereting at rated conditions. If the half-load armature current of the motor in Prob. 11.1 is 40 A, determine all copper losses. The field-circuit resistance and armature-circuit resistance of a 10- hp 115-V motor are 90 2 and 0.08 I1, respinctively. Determine the electrical power converted to mechanital power whan the motor draws SK) A from the line.

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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. A Short Shunt Compound DC Generator supplies 100-amp at 110-volt. Series field resistance of 0.04-ohm, armature resistance is 0.05-ohm, shunt field resistance of 57- ohm. Iron and friction losses mount to 852-watts. Find the power input and the over all efficiency.
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Q18 / Draw The torque-speed characteristic of a series DC motor.
A 400 V series motor has a field resistance of 0.02 ohm and an armatureresistance of 0.1 ohm. The motor takes 30 A of current at 1000 rpm whiledeveloping full load torque. What is the motor speed when this motordevelops 60 % of full load torque and the shunt is shunted by a resistorof 0.03 ohm? [Ans. 1294.98 rpm]
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