How Soft Starters Work？

How Soft Starters Work

The working principle of the soft starter is as follows: when the motor is started with the soft starter, the output voltage of the thyristor gradually increases, and the motor gradually accelerates until the thyristor is fully turned on. The motor works on the mechanical characteristics of the rated voltage, so as to achieve smooth start, reduce the starting current, and avoid starting over-current tripping. When the motor reaches the rated speed and the starting process is over, the soft starter will automatically replace the completed thyristor with a bypass contactor to provide the rated voltage for the normal operation of the motor, thereby reducing the heat loss of the thyristor and prolonging the service life of the soft starter. Improve its work efficiency and avoid grid harmonic pollution. The starting methods of the soft starter include ramp boost soft start, ramp constant current soft start, step start, pulse impact start, voltage double-slope start and current-limited start.