SIMATIC direct starter — 3RK1301-0FB00-0AA2
The Siemens 3RK1301-0FB00-0AA2 is a SIMATIC direct starter motor starter, designed for direct-on-line starting of three-phase motors. The unit is pluggable on a terminal module, so it swaps without disturbing the power wiring.
Rated 50 kA at 400 V — that is the short-circuit breaking capacity at the main incoming supply level. For a panel fed from a 400 V transformer with an SCCR requirement above 50 kA, this starter coordinates cleanly without needing upstream fuses to clip the fault current. The 24 V DC control supply (20.4 to 28.8 V range) is standard for modern PLC cabinets; the unit pulls its logic power from the same 24 V bus as the rest of the SIMATIC I/O. Operating frequency is rated at a maximum of 750 1/h — that is about one start every 4.8 seconds. Fine for most conveyor and fan duty; not suited for high-cycle indexing or rapid reversing (reverse starting is explicitly not supported). Mounting is vertical or horizontal, and the 45 mm width and 120 mm depth fit standard 45 mm DIN-rail spacing.
Network integration — PROFINET and PROFIBUS DP
This starter supports both PROFINET and PROFIBUS DP protocols natively. The digital I/O map is 1 byte input and 1 byte output — enough for start/stop feedback, fault status, and a few diagnostic bits. No additional gateway or communication module is needed; it connects directly to the PLC via the network cable.
Shock resistance is 5 g for 11 ms, vibration resistance 2 g — suitable for panel mounting in industrial environments with moderate vibration. Degree of pollution is 3 at 400 V and 2 at 500 V per IEC 60664, which covers most factory floor conditions (conductive dust, occasional condensation).