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CAPACITOR TYPE SPLIT PHASE MOTORS

Capacitor type split phase motors are generally similar to the standard split phase construction except for the addition of capacitor and a slightly modified switching arrangement for the two value capacitor type motors. The three types of capacitor split phase motors have been shown in Figure.
Figure: Three types of capacitor type split phase motors

1) CAPACITOR START SPLIT PHASE MOTORS

These motors are used where high starting torque is required. To accomplish this, capacitors of large values are to be used. Electrolytic capacitors designed for short duty service are available and used in these motors. The motor should come upto its speed quickly and disconnect the capacitor from the windings, otherwise the capacitor will get damaged. The centrifugal switch or the relay that function in auxiliary winding should be very reliable.

2) PERMANENT SPLIT CAPACITOR MOTORS

These motors are mainly used for low starting torque loads where they are generally shaft mounted. Their particular fields of applications are in air moving equipment such as fans, blowers, oil burners etc. where quiet operation is required.

3) TWO VALUE CAPACITOR MOTORS

This type of capacitor motors has the advantage that they develop extremely high locked rotor torque with one value of capacitance in the auxiliary winding circuit and gives quiet running performance of the motor with another capacitor. Electrolytic capacitors are used for starting. Their values are 10 to 15 times as much as the value of the running capacitor.

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