The Siemens 3RK1322-1BS02-1AA3 is an AS-interface compact reversing starter in an IP65 enclosure — a self-contained motor control unit for reversing applications on a 400 V three-phase line. It's rated for 0.75 kW at AC-3 duty, meaning it handles the high inrush of a squirrel-cage motor during starting and reversing, not just resistive loads. The setting range of 1.4 to 2 A on the bimetal overload relay covers that motor current band. It communicates over AS-interface (the protocol is AS-interface, not PROFIBUS DP), and it includes two integrated inputs for local sensors or pushbuttons.
The enclosure measures 270 mm high, 120 mm wide, and 190 mm deep — a standalone box that bolts to a machine frame or a mounting plate. The main current circuit connects via tab terminals (9-pole motor outgoing feeder and 9-pole power connection), so you're looking at faston-style terminations, not screw clamps. The AS-i bus connection is a separate bus tap. For a reversing starter mounted out on the machine, that fault rating is what keeps a bolted short from cascading back into the line.