What are four windings in a AC compressor?

In an AC compressor, the four windings typically refer to the main components of the compressor's motor, which include the start winding, run winding, common winding, and a potential relay or capacitor winding. The start winding is energized briefly to help the motor start, while the run winding maintains the motor's operation. In some designs, a capacitor may be used to improve efficiency and starting torque. These windings work together to ensure the compressor operates effectively and efficiently.