What it is and what it does
The Siemens 3RK1303-6DS71-1AA0 is a reversing starter — a solid-state motor starter that handles direction reversal for three-phase induction motors up to 12 A in AC-3 duty at 400 V. That AC-3 rating means it's sized for starting and stopping squirrel-cage motors under load, not just resistive heating. The solid-state switching contacts give it a high electrical life; the auxiliary contacts are rated for fewer than 1 error per 100 million operating cycles, so it's built for high-cycle applications like conveyor reversals or shuttle movements. It's a fully integrated unit with short-circuit protection via fuses, full motor protection, and a 100 kA rated short-circuit withstand at 400 V — meaning it can safely clear a fault up to that level without upstream coordination failure. The operating voltage range is 400 to 500 V, and the control supply is 24 V DC, with a permissible range of 20.4 to 28.8 V.
Where it goes and how it connects
This is a field-mount unit, not a DIN-rail panel device. The IP65 rating means the enclosure is dust-tight and protected against low-pressure water jets — suitable for washdown areas on packaging lines, conveyors, or food-processing zones where you'd rather keep the starter close to the motor than in a remote panel. The main energy infeed and load-side outgoing feeder use sockets per ISO 23570, and the supply-voltage line-side connection is a hybrid plug. Communication uses a hybrid plug/socket pair for PROFIBUS DP. Two digital inputs are provided via M12 sockets, parameterizable for functions like start, stop, or direction selection. There are no digital outputs. The brake control for 400 V AC is not supported — if you need a DC brake, that's handled separately.