What is true about the start winding of a split-phase motor?

The statement about the start winding of a split-phase motor being true is that it has more turns of wire than the run winding. The reason for this design is primarily to create a higher impedance in the start winding compared to the run winding. A greater number of turns in the start winding generates a stronger magnetic field, which is essential for initiating the motor's rotation.

The increased number of turns creates a significant phase difference between the currents in the start and run windings. This phase difference is necessary to provide the required starting torque for the motor to overcome inertia and begin rotating. Once the motor reaches a certain speed, a centrifugal switch or relay typically disconnects the start winding from the circuit, allowing the motor to run efficiently on just the run winding.

This understanding of the winding configurations helps in diagnosing issues related to split-phase motors, particularly in identifying problems during the startup phase, something that is critical for HVAC applications and other systems utilizing split-phase motors.