What this part is and where it fits
The Siemens 3RK1322-0FS02-1AA4 is an AS-Interface compact reversing starter in the SIRIUS family — a fully integrated motor start and reversing contactor, overload protection, and bus interface in one IP65 enclosure. Rated for 0.12 kW at 400 V AC-3 (the motor switching duty class), it covers small reversing drives like conveyor reversers, gate actuators, or pump direction control where the line-side wiring stops at the starter and the motor connects through a 9-pole tab-terminal outgoing feeder. The IP65 rating means the housing and the tab-terminal connections tolerate washdown and dust — this is a machine-mount or line-side starter, not a panel-mount device. It lives on the machine frame or near the motor, not inside a control cabinet.
Key ratings and what they mean for fit
The setting range of 0.35 A to 0.5 A (bimetal overload) matches small three-phase motors — think fractional-horsepower drives in the 0.12 kW class. The 50 kA breaking capacity at 400 V means it clears a bolted fault up to that level without the upstream breaker needing to trip, which is unusually high for a starter this size and tells you the internal short-circuit protection (circuit-breaker design) is robust. The integrated brake contact (500 V DC / 1 A) handles a DC injection brake or holding brake on the motor shaft — common on vertical-load conveyors or tool spindles that need to hold position when power drops. The two integrated inputs on the AS-Interface bus let you wire local pushbuttons or sensors directly into the starter without an extra I/O module. Operating temperature range of -25 °C to +55 °C covers most factory-floor and outdoor sheltered installations. The 190 mm depth, 120 mm width, and 270 mm height define the footprint for machine-mount bracketing or a small junction-box enclosure.