The Siemens 3RK1300-0FS01-0AA4 is an EM 300 DS electromechanical direct starter designed for the ET 200X distributed I/O system. It is a motor protection and switching device that integrates a bimetal overload relay, a contactor, and a PROFIBUS DP communication interface into a single IP65-rated enclosure. The setting range is 0.35 to 0.5 A, matched to a motor rated 0.12 kW at 400 V in AC-3 duty (cage-induction motor switching). The operating voltage range is 400 to 500 V.
The AC-3 rating of 0.12 kW at 400 V is the motor-switching capacity — this part is sized for small three-phase motors up to that power. The 0.35 to 0.5 A setting range must match the motor full-load current; if your motor draws outside that window, this starter won't protect it. For higher fault currents, a circuit breaker or fuse upstream must coordinate. The part is not submersible. PROFIBUS DP protocol is built in, so the starter communicates directly on a PROFIBUS DP network without an extra gateway. No AS-interface support on this variant.
The integrated motor brake output (DC 500 V/1 A) allows direct control of an internally supplied brake — common on vertical-load axes or holding-brake motors.
No surplus or broker channel is needed.
Integration notes
Mounts in an ET 200X station; the 140 mm width, 270 mm height, and 134 mm depth determine the panel cutout and enclosure size. The 9-pole motor feeder and 9-pole power connection are pre-wired via the ET 200X backplane — no field wiring of the power bus is required.