What this part is and what it does
The Siemens 3RK1322-1KS02-1AA0 is a SIRIUS AS-Interface compact reversing starter in an IP65 enclosure — a self-contained motor-starting and reversing unit for three-phase induction motors up to 5.5 kW at 400 V AC-3 duty. It integrates an electromechanical reversing contactor, a bimetal overload relay, and short-circuit protection via circuit-breakers, all inside a housing rated IP65 for washdown or dusty environments. The setting range spans 9 to 12 A, and the unit communicates over AS-Interface (AS-i) protocol, with two integrated inputs for local sensors or pushbuttons.
Key ratings and what they mean for fit
The 5.5 kW rating at AC-3 (400 V) is the motor-switching capacity — it handles standard squirrel-cage induction motors up to that power, covering common conveyor, pump, and fan loads in a 400 V line. The 9-12 A setting range on the bimetal overload relay means the motor full-load current must fall within that window; if your motor draws 8 A or 13 A, this unit is not the right fit. The 50 kA short-circuit breaking capacity (Icu) at 400 V means the integrated circuit-breaker can safely interrupt a fault current up to 50,000 A without upstream damage — important for high-fault installations. The IP65 rating means the enclosure is dust-tight and protected against low-pressure water jets, so it can be mounted directly on a machine frame or in a washdown zone without a separate panel.
Where it is used and how it connects
This reversing starter is designed for decentralized motor control in automated production lines — think conveyor reversals, hoist direction changes, or valve actuators. It mounts directly on the machine frame (no enclosure needed) thanks to the IP65 housing. The main current circuit connects via tab terminals (9-pole motor outgoing feeder and 9-pole power connection), and the AS-Interface bus cable handles both power and communication to the PLC. The -25 to +55 °C operating range covers most factory-floor conditions, but derate if mounted in a sun-exposed or oven-adjacent location.