Siemens SIRIUS 3RW4427-3BC45 Soft Starter - 93A, 55kW

The Siemens SIRIUS 3RW4427-3BC45 is a soft starter designed for smooth and controlled acceleration of three-phase induction motors. It operates within a voltage range of 400-600V AC, with auxiliary control voltage at 230V AC, utilizing spring-type terminals for secure connections. For standard applications at 500V and 40°C, it supports a current of 93A and a motor power of 55kW. When connected inside the delta winding (inside-delta configuration), it can handle a higher current of 161A and motor power of 110kW.

This soft starter is suitable for a variety of applications where reducing mechanical stress and electrical inrush current is important, such as large pumps, fans, compressors, and conveyors. Its use helps to extend the lifespan of motors and connected machinery by minimizing shock loads during startup. Industries that benefit include general manufacturing, water treatment, and HVAC.

This is a phased-out product, with the SIRIUS 3RW5 series being its successor, and specifically the 3RW5527-3HA16 as the preferred successor type. Stanlo Automation, your veteran-owned source for surplus industrial automation parts, can help you find available stock of the 3RW4427-3BC45 or suitable alternatives for your critical applications.