What distinguishes a permanent split capacitor (PSC) motor from a capacitor-start motor?

The distinction between a permanent split capacitor (PSC) motor and a capacitor-start motor is fundamentally based on how each uses capacitors during operation. A PSC motor incorporates a capacitor that is connected to its windings at all times, providing both starting torque and continuous running efficiency. This design allows for smoother operation and better efficiency at lower speeds since the capacitor aids in creating a phase shift and improving the motor's power factor during both the starting and running phases.

In contrast, capacitor-start motors only utilize the capacitor at startup to provide an initial surge of torque. Once the motor reaches a certain speed, typically around 70-80% of full operating speed, a centrifugal switch disconnects the capacitor from the circuit, and the motor runs solely on its main winding. This means that, after starting, the capacitor-start motor does not benefit from the capacitor's advantages during normal operation.

Other options provide misconceptions about the differences: the idea that PSC motors only operate at lower speeds, that they require more complex wiring, or that they are less efficient does not accurately define their characteristics compared to capacitor-start motors. The real distinguishing factor is the continuous use of the capacitor in PSC motors vs. its temporary use in capacitor-start motors.