Reversing starter for ET 200 X — what the ratings mean for fit
The Siemens 3RK1300-0JS01-1AA0 is an electromechanical reversing starter from the SIRIUS EM 300 RS family, designed specifically for the ET 200 X distributed I/O system. It integrates a reversing contactor pair, bimetal overload relay, and PROFIBUS DP communication into a single IP65-rated enclosure — meaning it mounts directly on the machine or conveyor section, not in a central cabinet. The 0.25 kW rating at AC-3 duty (400 V) tells you it switches a standard 3-phase induction motor up to that load under full starting current; the 0.7–1.0 A setting range on the bimetal relay matches the motor full-load current within that band. For a 0.25 kW motor drawing roughly 0.7 A at 400 V, this starter is sized correctly — no headroom for a larger motor. The 50 A short-circuit breaking capacity at 400 V (Icu) means the integrated circuit-breaker-style protection can interrupt a fault up to that level without upstream devices needing to clear it — useful for selectivity in a distributed motor group. The 400–500 V operating voltage range covers standard European 400 V three-phase networks and North American 480 V systems. Tab terminals on the main circuit match the ET 200 X power bus; no screw-clamp wiring on the motor feeder. PROFIBUS DP onboard means this starter communicates directly with a PLC over the fieldbus — no separate gateway or I/O block needed for the reversing function. The 9-pole motor feeder and 9-pole power connection are pre-wired for the ET 200 X interface; the unit is a drop-in replacement for the same slot in that system.
Deployment context — distributed motor control
IP65 lets this starter live on the machine frame in washdown areas — food processing, packaging, or automotive assembly zones where a central panel would be impractical. The 270 × 140 × 134 mm (H × W × D) footprint fits the ET 200 X enclosure family; no additional junction box needed for the motor branch. Ambient operating range of 0–55 °C covers most production-floor environments without derating.