What this reversing starter does
The Siemens 3RK1322-0AS12-1AA0 is a reversing starter — a compact motor control unit that handles forward/reverse switching of three-phase motors up to its rated operating voltage of 400-500 V. It integrates solid-state motor protection, so it detects overload conditions electronically rather than relying on a thermal bimetal, which means faster trip response and no ambient-temperature derating issues.
Signal and control wiring
Two M12 digital inputs handle the start/stop and direction commands — one socket per input. The inputs are not parameterizable, so the wiring logic is fixed; you supply 24 V DC nominal (20.4-28.8 V operating range) through the AS-i shaped cable using the cutting/clamping method for both line-side supply and transmission. The main energy infeed and load-side outgoing feeder use sockets per ISO 23570, which is a standardized connector interface for motor starters. No PROFIBUS or PROFINET onboard, but the bus communication capability means it talks over the AS-i network.
Physical integration
The housing measures 270 mm high, 120 mm wide, and 190 mm deep. That width is narrower than a typical contactor-plus-overload combination, so it saves rail space in a panel. The front addressing socket lets you set the device address without opening the enclosure — useful when the unit is mounted in a hard-to-reach spot on a machine frame.