What is the function of the centrifugal switch on a split phase or capacitor start motor?

The function of the centrifugal switch in a split phase or capacitor start motor is to remove the start winding when the motor reaches a certain speed. This is critical because the start winding is only needed during the initial startup phase to create the necessary phase shift for proper motor operation. Once the motor's speed builds up to a predetermined level, the centrifugal switch opens the circuit to the start winding, effectively disconnecting it from the power supply. This prevents overheating and potential damage that could occur if the start winding continued to be energized while the motor runs at full speed, ensuring the motor operates efficiently and safely.

In this manner, the centrifugal switch plays a vital role in transitioning from startup to normal operation, thus maximizing the performance and longevity of the motor.