4.a. The stop control in a three-wire control scheme stops the motor by A. increasing the resistance in the run circuit. B. shorting the starter coil. C. tripping the thermal overloads. D. disrupting current flow to the coil. 4.b. An across-the-line starter does not change the speed of a squirrel-cage motor because it A. varies the internal rotor resistance. B. does not vary the line voltage. C. varies the line voltage as the line frequency increases. D. varies the pole connections at each setting.

4.a. The stop control in a three-wire control scheme stops the motor by A. increasing the resistance in the run circuit. B. shorting the starter coil. C. tripping the thermal overloads. D. disrupting current flow to the coil. 4.b. An across-the-line starter does not change the speed of a squirrel-cage motor because it A. varies the internal rotor resistance. B. does not vary the line voltage. C. varies the line voltage as the line frequency increases. D. varies the pole connections at each setting.

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter52: Direct Drives And Pulley Drives

Section: Chapter Questions

Problem 8SQ

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