What it is and what it does
The Siemens 3RK1300-1GS01-0AA1 is an EM 300 DS electromechanical direct starter designed for the ET 200X distributed I/O system. It combines a contactor, bimetal overload relay, and short-circuit protection into a single IP65-rated enclosure that mounts directly on the machine frame, not inside a control cabinet. The setting range of 4.5...6.3 A covers small induction motors up to 2.2 kW at 400 V in AC-3 duty — the standard category for starting squirrel-cage motors under load. That 2.2 kW rating is the motor power it can switch, not the load it carries continuously; the bimetal overload tracks motor heating and trips on sustained overcurrent.
Built-in brake contact and bus communication
A motor brake output is integrated — the DC 24 V / 3 A brake contact supplies an externally mounted holding brake, so the starter handles both the motor power and the brake release in one unit. That saves an external relay and simplifies wiring on vertical-axis or fast-stop axes. PROFIBUS DP is on board, letting the starter communicate directly with a PLC over the ET 200X backplane. No AS-Interface here — this variant is strictly PROFIBUS, which suits larger distributed lines where the bus length and speed matter more than the simplicity of AS-i.
IP65 and tab terminals — built for the machine, not the panel
Rated IP65, the housing is dust-tight and protected against low-pressure water jets — think washdown zones on a packaging line or coolant splash on a machining cell. The 9-pole motor feeder and 9-pole power connection use tab terminals, which mate with the ET 200X base unit; no screw terminals to torque inside the enclosure. Dimensions of 270 mm high × 140 mm wide × 134 mm deep fit the standard ET 200X footprint. Ambient operating range of 0...55 °C covers most factory-floor conditions without derating.