Page 120 - Electrician - TT (Volume 2)

ELECTRICIAN - CITS

Torque speed characteristics of split phase motor (Fig 3)

Capacitor start induction run motor. (Fig 4)
Torque speed characteristics (Fig 5)

In this motor a centrifugal switch is provided in series with the capacitor of capacitance of (60-120 micro farad).
The centrifugal automatically disconnect the starting winding when the motor attains 75% of its normal speed.
The starting winding of capacitor start induction motor is designed for short time ratings. It has good starting
torque even from low starting current and therefore suitable for driving compressors, pumps etc. Methods of
change of direction of rotation is similar to that of split phase induction motor.

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CITS : Power - Electrician & Wireman - Lesson 70-75 CITS : Power - Electrician & Wireman - Lesson 70-75