Autotransformer starters or compensators are sometimes used with polyphase induction motors to _____________. A. reduce the voltage applied to the motor during the starting period B. increase the voltage for 'across-the-line starting' C. provide a backup means of voltage regulation for emergency starting D. allow the voltage to be either stepped up or down, depending on the application, to ensure full torque

Autotransformer starters or compensators are sometimes used with polyphase induction motors to _____________. A. reduce the voltage applied to the motor during the starting period B. increase the voltage for 'across-the-line starting' C. provide a backup means of voltage regulation for emergency starting D. allow the voltage to be either stepped up or down, depending on the application, to ensure full torque
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Answer: A
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Last Answer : Answer: B

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Last Answer : Answer: A

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Last Answer : Answer: D

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If a three-phase induction motor is operated under a light load and it develops an open in one of its supply lines, the motor will _____________. A. continue to run, but will vibrate and have reduced torque B. speed up due to the reduced number of poles C. run cooler due to reduced current flow D. stop

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The purpose of amortisseur windings in a synchronous motor is to ______________. A. reduce eddy current losses B. produce a higher power factor C. provide a means for starting D. eliminate arcing between the stator and the rotor

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Last Answer : Ans: B

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Last Answer : Answer: C

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