How does a capacitor start motor differ in design from a split phase motor?

A capacitor start motor is specifically designed to utilize a start capacitor that is wired in series with the start winding. This configuration is intended to provide an additional phase shift, which enhances the starting torque of the motor. The presence of the capacitor allows the motor to generate a stronger magnetic field during startup, enabling it to overcome inertia and start under load more effectively compared to a split phase motor.

In contrast, a split phase motor typically has two windings—a start winding and a run winding—but does not incorporate a capacitor in its design. The split phase motor relies on the difference in resistance and inductance between the two windings to create the necessary phase difference for starting, which results in less starting torque compared to a capacitor start motor.

Understanding this fundamental difference in the design helps clarify the operational capabilities of each type of motor, particularly in applications requiring high starting torque. The capacitor's role in the capacitor start motor is crucial for enhancing performance during startup, setting it apart from the simpler split phase design.