Siemens SIRIUS 3RW4458-6BC35 Soft Starter - 850A, 950hp

The Siemens 3RW4458-6BC35 is a SIRIUS soft starter designed for smooth starting of three-phase motors. At a standard 575V and 50°C ambient temperature, it can handle 850 Amps and is rated for 950 hp. When configured in an inside-delta circuit, its capacity increases to 1472 Amps, suitable for up to 1650 hp motors. The device operates on a control voltage of 115V AC and a power circuit voltage range of 400-600V AC. It features screw terminals for reliable connections.

This soft starter is crucial for applications requiring reduced mechanical stress on motors and machinery during startup. It minimizes inrush current, thereby protecting the electrical supply system and extending the life of motor components. It is commonly used in heavy-duty industrial applications such as conveyors, pumps, compressors, and fans where high starting torque is required but a soft start is beneficial for system stability and longevity.

Stanlo Automation, a veteran-owned surplus parts distributor, offers the Siemens 3RW4458-6BC35 SIRIUS soft starter. Please note this is a phased-out product, with the preferred successor being the 3RW5556-6HA16. Secure this reliable component for your applications while available.