Some information:
Capacitor Start Motors:
The capacitor start motor is essentially the same as a split phase motor where the two windings are out of phase with each other, providing the necessary torgue for starting the motor to rotate. The addition of the capcitor in series with the start winding adds to the initial torque and causes the current in that winding to lead the running winding phase voltage, obtaining a greater angle of displacement between the start and running windings. In a capacitor start motor the starting winding and the capacitor are disconnected by centrifugal switch.
Capacitor Run Motors:
The capacitor run mtor design is ver similar to the capacitor start motor. A capacitor run motor has the starting winding and the capacitor in series at all times. Because the capcitor remains in the circuit at all times, a lower value of capcitor is used. The capacitor run mtor has a higher running torque than a capacitor start motor. In a capacitor run motor, the capacitor remains in the circuit while the motor is running.
Capacitor Start and Run Motors:
Capacitor start and run motors combine the advantage of the capcitor start motor which has high starting torque with that of the capacitor run motor which has high running torque. the capacitor start and run motor starts with a high value and a low value capacitor connected in parallel with each other but in series with the starting winding. This provides a very high starting torque. The centrifugal switch disconnects the high value capacitor at eighty percent speed, but the lower value capacitor remains in the cricuit.
In a capcaitor start and run motor the staring capacitor is disconnected when the motor reaches speed but the running capacitor remains in the circuit.