6.3 A reversing starter with AS-Interface bus
The Siemens 3RK4320-3LQ54-1BA2 is a SIRIUS reversing motor starter with integrated AS-Interface communication, rated 6.3 A at AC-3 400 V — this is the motor-switching current for standard squirrel-cage induction motors, not the thermal full-load current.
Control supply and AS-Interface integration
The control supply is 20.4 to 26.4 V DC, and the unit supports AS-Interface protocol — no PROFIBUS or PROFINET on this variant. Two digital inputs are onboard for local start/stop or feedback.
Mounting and environmental fit
The enclosure measures 205 mm deep by 245 mm wide by 215 mm high, with IP54 protection — suitable for panel-mount in dry or damp industrial environments, not washdown. The unit includes a motor brake output (24 V DC brake control is not present; brake control options for 180 V DC, 400 V AC, and 500 V DC are all listed as 'no').