What this part is and where it fits
The Siemens 3RK1300-0HS01-0AA1 is an EM 300 DS electromechanical direct starter designed for the ET 200X distributed I/O system. It combines a contactor, bimetal overload relay, and short-circuit protection (circuit-breaker style) into one IP65-rated enclosure — meaning it lives directly on the machine, not in a central panel. The setting range of 0.55...0.8 A covers small motors up to 0.21 kW at AC-3 duty on a 400...500 V supply. This is a field-mount unit: IP65 lets it sit on a conveyor frame or machine skid without an additional cabinet. The 9-pole motor feeder and 9-pole power connection mean it plugs into the ET 200X backplane, so wiring is a matter of snapping it onto the rail and connecting the motor cable via tab terminals.