SIRIUS 3RW Soft Starters


The Ideal Soft Starter for Every Application

SIRIUS 3RW soft starters are a cost-effective alternative to using direct or wye-delta starters for starting three-phase motors. They avoid undesirable side effects such as mechanical bumps in the machine and mechanics or voltage drops in the mains supply. The soft start in control cabinets can be implemented in almost any application in a simple and practical way with our complete soft starter range.


SIRIUS 3RW Soft Starters


SIRIUS 3RW30 for Standard Applications

Belt slip on heater blowers or a sudden buildup of water pressure in washing installations are only two of the many problems that can occur when motors generate too much power on starting. With the SIRIUS 3RW30 from 1.5 kW to 55 kW (at 400 V) you can easily avoid such problems. And the best of it all is: It is also possible to switch straight from direct to soft start because SIRIUS 3RW30 is the only soft starter in the world that offers identical sizes in a family of devices.

Advantages at a glance
  • Soft start

  • Stepless starting

  • Uniform connection system with screw or spring-
    loaded terminals

  • Space-saving clear cabinet design thanks to its
    small and compact construction

  • Integral bypass

  • Reduction of current peaks

  • Relief of the power supply network

  • Reduction of the mechanical load in the drive

  • Simple and fast startup and maintenance

SIRIUS 3RW40 for Standard Applications

SIRIUS 3RW40 is the star among our standard soft starters. Thanks to its innovative control method, it is not just the only 2-phase-controlled soft starter in the world for use in the power range up to 250 kW (at 400V) – respectively 300 hp (at 460V) – because of its especially compact design, it ensures a space-saving, clear layout in the control cabinet. It is therefore more than a mere functionally expanded addition to our 2-phase-controlled series of SIRIUS 3RW30/31 soft starters.

The new 3RW40 soft starters in the lower power range from 5.5 - 55 kW (with 400 V) in sizes S0 to S3 expand the performance spectrum of the 3RW40 soft starters. They represent the compact and price-attractive alternative to start-delta starters.

Advantages at a glance
  • Uniform connecting system with screw or spring-loaded terminals

  • Space-saving, clear layout in the control cabinet thanks to small, compact design

  • Integrated bridging (bypass)

  • Inherent protection and protection against motor overload without additional wiring

  • Optional thermistor motor protection

  • Avoidance of peak inrush current thanks to adjustable current limitation

  • Simple and fast commissioning

  • Certified according to ATEX standards with sizes S0 - S12

3RW44 for High-Feature Applications

A compact design for maximum functionality

Thanks to its outstanding functions, the SIRIUS 3RW44 all-round talent handles difficult start-up and deceleration processes in a simple and, above all, gentle manner. With its innovative torque control system, it can be used for drives with a power output up to 710 kW at 400 V – respectively 950 hp at 460 V – in an inline circuit or up to 1200 kW at 400 V – respectively 1700 hp at 460 V – in an inside-delta circuit. Designed for simple handling, the functions are exceptionally easy to use.

Advantages at a glance

  • Optimum acceleration due to torque control

  • Simple and fast commissioning thanks to user-friendly display

  • Savings in size and costs due to optional inside-delta circuit

  • Simple integration in higher-level control units via PROFIBUS


 3RW30, 3RW40 for Standard Applications

3RW44 for High-Feature Applications
  • Soft Starter ES
  • Win-Soft Starter
  • PCS 7 block library