Find the following given the problem on the left: a. starting line current drawn by this motor at rated conditions b. output torque of the motor at rated conditions c. resistance that should be inserted in series with the armature circuit to limit the starting armature current to 200% or less of its rated value A 240-volt self-excited shunt DC motor has field resistance R, = 200 ohms and armature resistance R = 0.25 ohms. • No-load condition: The motor is run with a 240-volt DC source no load driven. The motor runs at 1800 RPM and draw 720 watts from the source. • Full-load condition: The motor is run with a 240-volt DC source while driving its rated load. The motor runs at 1700 RPM and draws 6400 watts. Neglect effects of saturation and assume that rotational power losses are constant for any load. Stray load losses for this motor are negligible. Answer the following questions for this machine.

Find the following given the problem on the left: a. starting line current drawn by this motor at rated conditions b. output torque of the motor at rated conditions c. resistance that should be inserted in series with the armature circuit to limit the starting armature current to 200% or less of its rated value A 240-volt self-excited shunt DC motor has field resistance R, = 200 ohms and armature resistance R = 0.25 ohms. • No-load condition: The motor is run with a 240-volt DC source no load driven. The motor runs at 1800 RPM and draw 720 watts from the source. • Full-load condition: The motor is run with a 240-volt DC source while driving its rated load. The motor runs at 1700 RPM and draws 6400 watts. Neglect effects of saturation and assume that rotational power losses are constant for any load. Stray load losses for this motor are negligible. Answer the following questions for this machine.

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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