A 120 V, 5.6 kW, 1900 rpm d shunt motor requires only 16 volts to send armature-full-load current through the armature when the armature is held stationary. Neglect the rotational losses. (a) Determine the armature current if full line voltage is impressed across the armature at starting. (b) Determine the value of the external resistance needed in series with the armature to limit the starting current to 1.5 times the full-load current. (c) The motor is coupled to a mechanical load by a belt and is delivering full load (V, =120 V, n=1900 rpm, I, = I, ratea). If the belt breaks, determine the speed of the motor. Assume that, due to armat reaction, the flux at full load is 9 % less than the flux when the motor is idling. (a) Armature current = A (b) Start-up resistance = (c) Idling speed = rpm

A 120 V, 5.6 kW, 1900 rpm d shunt motor requires only 16 volts to send armature-full-load current through the armature when the armature is held stationary. Neglect the rotational losses. (a) Determine the armature current if full line voltage is impressed across the armature at starting. (b) Determine the value of the external resistance needed in series with the armature to limit the starting current to 1.5 times the full-load current. (c) The motor is coupled to a mechanical load by a belt and is delivering full load (V, =120 V, n=1900 rpm, I, = I, ratea). If the belt breaks, determine the speed of the motor. Assume that, due to armat reaction, the flux at full load is 9 % less than the flux when the motor is idling. (a) Armature current = A (b) Start-up resistance = (c) Idling speed = rpm

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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