3-Phase Soft-Starter Replaces Star-Delta with Compact Module

Improved start/stop performance, higher number of start cycles, electronic motor protection, monitoring and diagnostics make the RSHL Smart soft-starter an all-in-one solution. Available in 220, 480 and 600VAC versions, it controls and protects three-phase induction motors rated up to 11kW such as those used in pumps, compressors, fans, hydraulic systems, conveyors and industrial machinery.

The unit controls two phases during normal operation, while the third phase is continuously connected to the load. Soft starting and soft stopping is achieved by controlling the motor voltage and, during normal running operation (<20A), the semiconductors are by-passed by internal electromechanical relays. Operating parameters are adjusted using a selector switch, push switch and dual potentiometers on the front panel.

Soft starting and stopping characteristics can be programmed with nine customisable (time and shape) voltage ramping profiles offering ramp-up times to 20s, initial torque from 20-50 percent and ramp-down times up to 10s. A current limiting starting option is also available.

The built-in, manually adjustable, electronic overload can be set for either a Class 10 or Class 20 trip characteristic, and for manual or automatic reset. The RSHL Smart soft-starter can also monitor motors for overheating (via a PTC input), phase loss, sequence and imbalance. As well as motor monitoring, the RSHL also monitors itself for overheating and internal failures. Eight LEDs on the front panel indicate the device status and alarms. In addition, there is an end-of-ramp auxiliary relay, and alarm auxiliary relay, and over-temperature protection.

All members of the RSHL family carry CE and RoHS marks, are cUL approved and rated to IP20 against dust and water ingress.