The Siemens 3RK1300-0DS01-1AA4 is an EM 300 RS reversing starter from the SIRIUS family, designed for distributed motor control in ET 200X environments. It's a self-contained electromechanical unit rated at 0.09 kW at AC-3 duty on 400 V, with a motor current setting range of 0.22 to 0.32 A via bimetal overload protection. The IP65 enclosure means it handles washdown and dust ingress directly on the machine frame — no separate panel needed for this motor branch.
PROFIBUS DP and brake contact onboard
Bus communication is built in — PROFIBUS DP protocol on the unit, so the reversing starter talks directly to the PLC without an external gateway. That saves a network node and simplifies the wiring harness. The motor brake output (DC 500 V / 1 A) is integrated for internally supplied brakes, which is common on small conveyor and handling axes that need a holding brake. The 9-pole motor feeder and 9-pole power connection mate via tab terminals on the main current circuit.
What the ratings mean for fit
The 0.09 kW at AC-3 / 400 V rating tells you this is sized for a small three-phase motor — think a 0.09 kW conveyor drive or a positioning axis. The 0.22 to 0.32 A setting range matches the full-load current of a motor in that power band. The 50 A maximum short-circuit breaking capacity (Icu at 400 V) means the unit's internal circuit-breaker coordination can interrupt a fault up to that level without upstream gear having to clear it. Operating voltage is 400 to 500 V, so it's at home on standard European 400 V three-phase networks. Ambient temperature range of 0 to 55 °C covers most industrial hall conditions, but not freezer applications.