The Siemens 3RK1322-0JS02-1AA1 is a SIRIUS AS-i compact reversing starter — an IP65-rated, self-contained motor control unit that integrates the reversing contactor, bimetal overload relay, short-circuit protection via circuit-breakers, and AS-interface bus communication into a single enclosure. It is designed for direct-on-line reversing control of small three-phase motors up to 0.25 kW at 400 V AC-3, with a setting range of 0.7 to 1 A. The unit includes a motor brake output (24 V DC / 3 A) and two integrated inputs, making it a drop-in solution for distributed motor control in AS-i networks.
What the ratings mean for fit
The 0.25 kW AC-3 rating at 400 V is the motor switching capacity under standard induction motor starting conditions — this is the figure that governs the motor size it can handle, not the thermal current. The 0.7 to 1 A setting range on the bimetal overload matches the full-load current of a motor in that power band; set it to the motor nameplate FLA. The IP65 enclosure means the entire unit — contacts, overload, and bus electronics — withstands washdown and dust ingress, so it mounts directly on the machine frame or conveyor line without a separate panel. The 50 kA short-circuit breaking capacity at 400 V (Icu) is the fault current it can safely interrupt; coordinate upstream protection to stay within that limit.
Integration and connectivity
This starter communicates over AS-interface (AS-i protocol), not PROFIBUS DP — verify your network master supports AS-i. The main current circuit connects via tab terminals, typical for IP65 field-mount units; the 9-pole motor outgoing feeder and 9-pole power connection are pre-wired for quick hookup. The integrated brake output (24 V DC / 3 A) controls a motor holding brake directly, saving an external relay. Two integrated inputs accept limit switches or sensors. Ambient operating range is -25 to +55 °C, so it suits unheated production areas or outdoor cabinets within that span.