Motor starter for AS-Interface reversing duty
The Siemens SIRIUS 3RK4320-3HQ54-1BA2 is a reversing motor starter designed for AS-Interface bus communication, rated 3.2 A at AC-3 duty on a 400 V supply. Operating voltage is 340 to 440 V AC, 50/60 Hz, with a DC control supply of 20.4 to 26.4 V. The unit includes a motor brake output and two digital inputs, making it suitable for reversing applications where a single contactor-based solution must handle forward/reverse direction changes under AS-Interface control. The IP54 enclosure protects against dust ingress and splashing water, so the starter can be mounted inside a control cabinet or in a protected machine enclosure where washdown is not direct.
Bus integration and I/O
AS-Interface is the only fieldbus protocol supported — PROFINET and PROFIBUS DP are not available on this variant. The two digital inputs can be mapped to AS-i slave data for local pushbuttons or limit switches, reducing wiring back to a central PLC. Dimensions are 245 mm wide by 215 mm high by 205 mm deep — factor this into DIN-rail spacing and enclosure depth.