The Siemens 3RK1300-1FS01-0AA4 is an EM 300 DS direct starter from the SIRIUS family, designed for the ET 200X distributed I/O system. It's an electromechanical direct-on-line starter with a bimetal overload relay, rated for AC-3 duty at 1.9 kW at 400 V and a setting range of 3.5 to 5.0 A. The IP65 enclosure means this unit is built to handle washdown environments — think food processing, packaging lines, or any spot where a hose-down is part of the routine. The integrated motor brake output handles DC 500 V/1 A for internally supplied brakes, saving you an external contactor on the brake circuit.
At 140 mm wide and 270 mm tall, this starter occupies a standard footprint for the ET 200X family. The 134 mm depth is important for shallow enclosures — verify your gland plate clearance before committing the BOM line. Operating voltage is 400 to 500 V AC, so it's happy on 400 V or 480 V systems without a transformer tap change. Short-circuit protection is handled by circuit-breakers (the unit is designed for coordination with them, not fuses). Ambient temperature range is 0 to 55 °C during operation; if your panel sits in a hot machine cabinet or near a furnace line, you'll need to derate or add ventilation above that ceiling.
PROFIBUS DP and brake integration
This starter communicates over PROFIBUS DP, making it a drop on the fieldbus for remote start/stop and fault feedback. No AS-interface on this variant — the protocol is fixed at PROFIBUS. The integrated brake output is a real time-saver on the wiring side: it's rated for DC 500 V/1 A, which covers most small holding brakes on motors up to 1.9 kW. Equipment marking per DIN EN 61346-2 is Q, meaning it's classified as a switching device in the schematic.