What it is and what it does
The Siemens 3RK1300-0FS01-1AA0 is an electromechanical reversing starter from the SIRIUS EM 300 RS family, designed for the ET 200X distributed I/O system. It integrates motor starting, reversing, and bimetal overload protection in a single IP65 enclosure, rated for direct-on-line reversing duty up to 0.12 kW at AC-3 / 400 V. The setting range of 0.35 to 0.5 A covers small motors in that current band; the 50 A short-circuit breaking capacity at 400 V means it can clear a fault up to that level without upstream devices needing to intervene. PROFIBUS DP onboard gives the starter direct fieldbus communication for start/stop, reversing, and feedback — no separate gateway needed.
Where it goes
This is a panel-mount or machine-mount unit, not a DIN-rail component. The IP65 rating means it can be mounted directly on the machine frame or in a washdown zone — the enclosure and optics withstand hose-directed water and dust ingress. Main circuit connections use tab terminals, typical for the ET 200X ecosystem. The 9-pole motor feeder and 9-pole power connector are integral; no brake contact output is fitted on this variant. Dimensions are 140 mm wide, 270 mm high, 134 mm deep — check the gland plate clearance before committing the cutout.