Question 144Electricity & Electronics - QMED

70% to pass

If the centrifugal switch or relay used for cutting out the starting winding of a split- phase induction motor fails to open once the motor is in operation, what will be the result?

Athe motor torque will be above normal at rated speed
Bthe starting winding will burn out
Cthe motor will immediately stall under load
Dthe motor will overspeed
AI Explanation

The correct answer is B) the starting winding will burn out. If the centrifugal switch or relay fails to open the starting winding circuit once the motor reaches operating speed, the starting winding will remain energized. This will result in excessive current flowing through the starting winding, causing it to overheat and eventually burn out. The motor will continue to run on the main winding, but the loss of the starting winding will significantly reduce the motor's starting torque and overall performance. The other options are incorrect because: A) the motor torque would not be above normal, as the loss of the starting winding would reduce the overall torque; C) the motor would not immediately stall, as it would continue to run on the main winding; and D) the motor would not overspeed, as the main winding would still provide the appropriate operating speed.

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