Siemens SIRIUS 3RW Soft Starter, 250 kW, 480 V ac, 3 Phase

SIRIUS 3RW52 Soft Starter

Soft starter SIRIUS 3RW52 General Performance for simple applications for soft starting and stopping of three-phase asynchronous motors.
Soft starting, reduction of current peaks, prevention of supply voltage fluctuations during startup, reduction of load on the power supply network, reduction of mechanical load in the drive, considerable saving of space and wiring compared to star-delta (wye-delta) starters and frequency converters, maintenance-free switching and extremely easy handling. The integrated bypass allows a very compact construction, saves energy and ensures low heat dissipation in the control cabinet. Intelligent monitoring functions protect the soft starter against overheating and the motor against overload. In addition, you can limit the current during startup to a settable maximum value.

Thanks to 3-phase control, particularly suitable for high motor outputs and inside-delta circuits. The innovative Soft Torque function ensures that the motor is started gently. With the integrated remote reset, you can quickly and easily clear faults from a remote location. Worldwide approvals (e.g. IEC and UL/CSA).

The General Performance 3RW52 soft starters are available for supply systems up to 600 V in a wide performance range up to 560 kW with 24 V or 110-250 V supply voltages and all with both screw and spring-type terminals. Different device versions are available for analog output and thermistor motor protection.

Optional plug-in communication modules allow connection via PROFINET, PROFIBUS and Modbus TCP. Various HMI modules are available for installation in the device or the control cabinet door.

SIRIUS 3RW5 soft starters - As flexible as your tasks.

Features and Benefits

• Simple and fast commissioning


• Parameterization using potentiometers


• Wide range for control supply and main voltage


• Three-phase controlled for optimal motor start


• Parameterization with rotary potentiometer


• A wide range of communications interfaces (PROFINET, PROFIBUS, EtherNet/IP, Modbus)