3RW5548-6HA14, Soft Starter, 315 kW, 570 A, 200 to 480V AC

Siemens 3RW55 Soft Starter Series – Overview

Siemens 3RW55 soft starters are heavy-duty motor starting solutions designed for high-power industrial applications requiring robust and reliable control of three-phase asynchronous motors. The 3RW55 series focuses on reducing mechanical stress, limiting inrush current, and supporting very high motor power ratings with advanced motor protection and monitoring capabilities. With a rugged design and suitability for demanding operating conditions, Siemens 3RW55 soft starters are well suited for large pumps, compressors, crushers, conveyors, mills, and other heavy industrial machinery where dependable motor starting and long-term reliability are critical.

Product Description: 3RW5548-6HA14

The Siemens 3RW5548-6HA14 is a SIRIUS 3RW55 soft starter specified for heavy industrial motor starting. It is rated for a continuous operational current of 570 A and a motor power rating of 315 kW at 400 V (40 °C). The unit accepts a three-phase supply voltage from 200 to 480 V AC and is driven by a control supply of 110–250 V AC, making it compatible with common medium- and low-voltage plant supplies. Typical motor compatibility includes large three-phase asynchronous motors in the 250–400 kW band (400 V systems), which covers pumps, large compressors, conveyor drives and similar heavy-duty applications where soft starting reduces mechanical stress and limits inrush current.

Standout, verified features for this model include an integrated bypass contact system to minimise heat dissipation and conduction losses during run, support for an HMI high-feature module for local parameterising, and the option to fit a PROFINET communication module for networked monitoring and control. The 3RW5548-6HA14 offers adjustable start/stop ramps, current limiting and built-in motor monitoring functions (including ground-fault monitoring and configurable current-unbalance limits) that help protect motors and reduce downtime in demanding industrial environments. This combination of high rated current, wide supply-voltage compatibility and modular communication/HMI options makes the 3RW5548-6HA14 well suited to engineering procurement teams specifying robust soft starters for heavy plant installations.

Key Soft Starter Attributes