The Siemens 3RK1300-0BS01-1AA1 is an electromechanical reversing starter from the EM 300 RS family, designed for the ET 200X distributed I/O system. That IP65 rating lets it sit on a conveyor section or packaging cell where washdown hoses are routine.
Rated 0.06 kW at AC-3 duty at 400 V, this starter is sized for small reversing loads — think 0.06 kW motors on indexing conveyors, diverters, or small actuators. The bimetal overload relay sets between 0.14 A and 0.2 A, so the motor full-load current must fall within that narrow window; there's no room to fudge the setting. The 400...500 V operating voltage covers standard European 400 V three-phase networks and 480 V North American lines, but note the 50 A maximum short-circuit breaking capacity (Icu) at 400 V — upstream protection must coordinate to keep fault energy below that level. The integrated motor brake output handles a DC 24 V / 3 A brake, externally supplied — common for small holding brakes on vertical-axis motors or quick-stop applications. That saves an external brake rectifier and relay, which is one less SKU on the BOM.
Communication and control
PROFIBUS DP onboard means this starter talks directly to a PLC without a separate gateway or remote I/O block. The 9-pole motor feeder and 9-pole power connection handle both the motor leads and the brake wiring through a single connector — tab terminals for the main circuit. Wiring is straightforward: one cable from the starter to the motor, one PROFIBUS drop to the controller.
Physical integration
Dimensions: 270 mm high, 140 mm wide, 134 mm deep. That's a compact footprint for an IP65 reversing starter with communication — it fits a standard 300 mm wide fieldbox with room for cable glands. The tab terminals accept fork or ring lugs; no DIN-rail mounting here — it bolts directly to a backplate or mounting bracket.