The Siemens 3RK1315-6KS41-2AA3 is a SIRIUS direct motor starter designed for on-site operation in industrial automation. It's a self-contained unit — rated 0.75 kW at 400 V and 0.7 hp at 460/480 V — with a CLASS 10 trip curve, meaning it will disconnect a locked-rotor motor within 10 seconds at its rated current. That's the standard protection for standard induction motors driving pumps, fans, and conveyors. Power is supplied at 24 VDC nominal (20.4 to 28.8 V range), and the main circuit connects via a HAN Q4/2 plug per ISO 23570. Four digital inputs are available on an M12 plug for device addressing. Communication is over AS-Interface — no PROFIBUS DP or PROFINET on this variant, so if your control layer uses those fieldbuses, you'll need a gateway or a different module.
Mounting and environment — what fits where
This starter measures 294 mm wide, 215 mm high, and 159 mm deep. It's screw-fixed, not DIN-rail snap-on, so plan for four mounting points in the panel or on the machine frame. The unit can be mounted vertically, horizontally, or flat — but the recommended orientation is horizontal. Shock resistance is 12g at 11 ms, vibration resistance is 7 mm at 2g. That's enough for most machine-mounted applications — think conveyor drives or small pump skids — but if the starter will be on a high-vibration press or crusher, you may want to add damping mounts.
Switching behaviour and control logic
This is a direct starter only — no reversing capability. ON-delay is 85 ms, OFF-delay is 65 ms. Those are built-in, not configurable. The unit has 4 digital inputs for control signals; the assignment type is 2, which typically means two-wire control with a start/stop pair per the SIRIUS system architecture. If your application needs reversing or a longer delay, this isn't the variant — you'd step up to a reversing SIRIUS starter or add an external contactor.