A three-terminal manual starting rheostat has a resistance of 5.2 ohms in its starting resistor. The holding coil resistance is 10 ohms. This starting rheostat is connected to a shunt motor. The resistance of the armature is 0.22 ohm; the resistance of the shunt field is 100 ohms. The line voltage is 220VDC. a. What is the starting surge current taken by the motor? b. What is the current in the holding coil with the moveablew arm in the run position? c. What is the CEMF with the movable arm in the on position if the armature current is 20 amps?

A three-terminal manual starting rheostat has a resistance of 5.2 ohms in its starting resistor. The holding coil resistance is 10 ohms. This starting rheostat is connected to a shunt motor. The resistance of the armature is 0.22 ohm; the resistance of the shunt field is 100 ohms. The line voltage is 220VDC. a. What is the starting surge current taken by the motor? b. What is the current in the holding coil with the moveablew arm in the run position? c. What is the CEMF with the movable arm in the on position if the armature current is 20 amps?

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter43: About Dc Motors

Section: Chapter Questions

Problem 1SQ

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