A centrifugal switch is used to dis- connect 'starting winding when motor has___________?
Correct answer: C. picked up about 50 to 70 per cent of rated speed
- A. run for about 1 minute
- B. run for about 5 minutes
- C. picked up about 50 to 70 per cent of rated speed
- D. picked up about 10 to 25 per cent of rated speed
Explanation
The starting winding is needed only during acceleration, so the centrifugal switch opens it after the rotor reaches roughly 50 to 70 percent of rated speed. This prevents unnecessary heating and losses in the auxiliary winding.
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