CONNECTION OF MOTOR START CAPACITORS:
Among various types of single phase motors, the motor start capacitor is the most widely used type. In this type of motor, the starting torque is achieved by connecting a capacitor in series with the starting winding. A higher torque is obtained with a lower starting current, when compared to other types of single phase motors.
These motors are therefore eminently suited for apparatus having heavy starting duty. Motor start capacitors are fitted with a centrifugal switch which automatically disconnects the auxiliary winding when the motor attains a pre-determined speed and therefore works only with the help of the main winding (Refer Circuit). The capacitor is marked with two voltages (230/275) the higher voltage being the surge voltage and lower voltage being the rated peak operating voltage. The capacitor dielectric is built on to withstand this voltage only and a higher voltage likely to cause rupture. The surge voltage rated must be adequate for the maximum RMS value experience with motor concerned.