Siemens is a German industrial giant with over 170 years of history. The Siemens SIRIUS soft starter lineup includes three series: 3RW30 (compact, up to 55 kW), 3RW40 (mid-range, up to 250 kW), and 3RW44 (full-featured, up to 710 kW).

SIRIUS 3RW30 — Compact Starting

Siemens 3RW30 soft starters are the most compact in the SIRIUS lineup. Power range up to 55 kW at 400 V. Easy installation and setup. Optimal for standard applications: fans, small pumps, conveyors.

SIRIUS 3RW40 — Extended Protection

Siemens 3RW40 soft starters cover range up to 250 kW. Extended protection set: overload, phase imbalance, rotor lock. Adjustable ramp-up and stop times. Suitable for industrial facilities with medium and large motors.

SIRIUS 3RW44 — Maximum Features

The top-tier Siemens 3RW44 series features built-in bypass contactor, adaptive torque control, Profibus and Profinet interfaces, range up to 710 kW. Integration with Siemens TIA Portal automation system. Ideal for heavy-duty starts and critical applications.

Siemens Soft Starter Advantages

All series operate in the 200–690 V voltage range. Global service and support network. Compatible with Siemens VFDs and other SIRIUS ecosystem equipment. 24-month manufacturer warranty.

Frequently Asked Questions

What is the difference between Siemens SIRIUS 3RW30, 3RW40 and 3RW44?

3RW30 is a compact series for standard applications up to 55 kW. 3RW40 is a mid-range series with extended protection up to 250 kW. 3RW44 is the top series with full functionality: adaptive control, Profibus/Profinet interfaces, up to 710 kW.

What motors are compatible with Siemens soft starters?

Siemens SIRIUS soft starters are designed for three-phase asynchronous motors. 3RW30: up to 55 kW, 3RW40: up to 250 kW, 3RW44: up to 710 kW. Voltage 200–690 V. Applications: pumps, fans, compressors, conveyors.

Do Siemens soft starters have a built-in bypass?

The 3RW44 series has a built-in bypass contactor. The 3RW30 and 3RW40 series require an external bypass to reduce heat dissipation after ramp-up.

What warranty is available for Siemens soft starters?

Manufacturer warranty is 24 months. We provide technical support, selection assistance and service across Ukraine. Siemens soft starter service life is 15–20 years.