A star delta starter is the most commonly used method for the starting of a 3 phase induction motor. In star delta starting an induction motor is connected in through a star connection throughout the starting period. Then once the motor reaches the required speed, the motor is connected in through a delta connection.
A star delta starter is a type of reduced voltage starter. We use it to reduce the starting current of the motor without using any external device or apparatus. This is a big advantage of a star delta starter, as it typically has around 1/3 of the inrush current compared to a DOL starter.
The advantages of star delta starters are:
- No need for expensive and advanced equipment.
- The starter does not heat up, no switching devices need to be used.
- The value of the starting peak current is 1/3 of the direct starting current.
- Generates a large torque relative to the line current.
But remember, starting torque is reduced to 1/3 of full load torque.
