Connecting a PSC Motor for a Change of Speed

The PSC motor is available as a variable-speed motor. Since the PSC motor does not require a centrifugal switch, it does not have an end plate or access plate. Instead, all the leads that the motor has provided are brought out of the motor together near the end plate. These leads are generally color coded to identify their speed. Fig. 1b shows a diagram for a multispeed PSC motor. The color leads are connected at various points along the run winding coil. If power is applied at the very end of the run winding, all the poles of the run winding are used, and the motor will operate at its lowest speed. If power is connected at the terminal marked high speed, only one of the poles is used, and the motor will operate at its highest speed. Note that the motor will lose torque as its speed is increased because fewer windings are used to gain the extra speed.