What it is and what it does
The Siemens 3RK1315-6NS71-2AA0 is a SIRIUS direct motor starter — a self-contained unit combining a contactor and overload relay in one IP65 housing, ready for on-site operation without an enclosure. It's sized for a 4 kW motor at 400 V (5 hp at 480 V) and carries a Class 10 trip curve, meaning it allows up to 10 seconds of locked-rotor current before tripping — standard for general-purpose induction motors driving pumps, fans, or conveyors. The 24 VDC control supply (20.4 to 28.8 V range) powers the AS-Interface bus interface and four digital inputs, all addressed via an M12 plug. No PROFINET or PROFIBUS DP here — this is an AS-i node, period.
Mounting and environment
Screw-fixed to a machine frame or panel wall — no DIN rail. The 294 mm width by 215 mm height by 159 mm depth footprint fits in a standard electrical cabinet, but the IP65 rating means it can also mount directly on the machine, exposed to washdown or dust. Pollution degree 3 (conductive or dry non-conductive pollution) covers industrial environments. Mounting position is flexible: vertical, horizontal, or flat, though horizontal is recommended for best thermal performance. Rated for -25 to +55 °C operating ambient, with storage and transport down to -40 °C. Shock rated at 12g for 11 ms, vibration at 7 mm / 2g — tough enough for machine-mounted duty on presses or conveyors.