What is the purpose of a run capacitor in a single-phase motor?

The purpose of a run capacitor in a single-phase motor is to improve the motor's efficiency and power factor during operation. When a single-phase motor runs, it generates a rotating magnetic field, which is essential for its operation. The run capacitor creates a phase shift in the current, allowing for a more effective and balanced magnetic field. This enhances the motor's performance by minimizing the loss of energy and improving power factor, which is a measure of how effectively the motor converts electric power into mechanical power.

In contrast, while a run capacitor does not directly provide initial torque (this function is typically handled by a start capacitor), it plays a critical role once the motor is up and running, hence its designation. It also does not primarily function to reduce wear on components or manage temperature, as these aspects are controlled through other strategies and components. The focus of the run capacitor is on maintaining efficient operation during the motor's continuous running phase.