Question 145Electricity/Electronics - QMED70% to pass
A single-phase capacitor-start induction motor starts, comes up to about 75% rated speed, slows down to a lower speed, and accelerates again. Where is the problem most likely to be?
AI Explanation
The correct answer is C) running winding.
The issue you described, where the motor starts, reaches around 75% of its rated speed, then slows down before accelerating again, is likely caused by a problem with the running winding. This could be due to a failure or degradation in the running winding, which is responsible for maintaining the motor's speed once it has started.
The other options are less likely to be the source of the problem. The centrifugal switch (A) is responsible for switching the motor from the starting winding to the running winding, so a problem with it would typically prevent the motor from starting at all. The starting capacitor (B) and starting winding (D) are only involved in the initial startup process, not the ongoing operation of the motor.
Related Questions
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