Siemens SIRIUS 3RW Family | 3RW30/40 Series — Basic Performance Soft-Starters for Standard Applications:
SIRIUS 3RW30/40 soft starters are the world’s most compact two-phase controlled soft starters in the power range from 1.5 kW (at 400 V) to 250 kW (at 400 V) thanks to their innovative control principle. Their compact design helps you save space in the control panel configurations. SIRIUS 3RW30/40 soft starters are the ideal solution for simple applications of all kinds. The 3RW soft starters should always be designed on the basis of the required rated operational current of the motor. The motor ratings listed in the selection and ordering data are rough guide values and designed for basic starting conditions (CLASS 10).
The SIRIUS 3RW30 Basic Performance soft starters are suitable for soft starting of three-phase asynchronous motors. Thanks to two-phase control, not only is the current kept at minimum values in all three phases throughout the entire starting time, but disturbing direct current components are also eliminated. This not only enables the two-phase starting of motors up to 55 kW (at 400 V) but also avoids the current and torque peaks which occur e.g. with wye-delta starters. The SIRIUS 3RW40 Basic Performance soft starters are suitable for the soft starting and stopping of three-phase asynchronous motors. Thanks to two-phase control, not only is the current kept at minimum values in all three phases throughout the entire starting time, but disturbing direct current components are also eliminated. This not only enables the two-phase starting of motors up to 250 kW (at 400 V), but also avoids the current and torque peaks which occur, e.g. with wye-delta starters. The SIRIUS 3RW40 soft starters are suitable for starting explosion-proof motors with "increased safety" type of protection EEx e according to ATEX Directive 94/9/EC.