Eaton Corporation: Soft start controllers

The DS6, which is available for current ranges from 40 to 180 amps, can be used to upgrade existing systems, and is designed to be wired in the 3-phase line feeding the 3-motor input leads. Using silicon controlled rectifiers (SCR) to ramp the voltage to the motor, the DS6 provides smooth acceleration and deceleration of the load. Once the motor is started, the internal run bypass contactor closes, resulting in the motor running directly across the line. The internal-run bypass contactor significantly reduces heat generation when compared to non-bypass starters. The bypass contactor directly connects the motor line and improves system efficiency by reducing internal power losses.