What it is and what it does
The Siemens SIRIUS 3RT1036-3AX00-0AA3 is a Size S2 power contactor built for switching motor loads in industrial control panels. Its AC-2 rating at 400 V is 22 kW, which covers wound-rotor motors and moderate-duty starting — the kind of load you see on conveyors, crushers, and pumps that need controlled acceleration. The AC-4 rating at 400 V is 41 A, covering inching, plugging, and reversing duty where the contactor opens under full load. It mounts on 35 mm DIN rail per EN 50022 using either screws or the snap-on latch, and it fits a standard panel opening at 55 mm wide, 112 mm tall, and 115 mm deep. The front face carries IP20 protection for basic finger safety; the terminal area is IP00, meaning live parts are exposed once the cover is off — standard for this class, but something to note during panel access.
Terminal and wiring detail
Main power terminals are screw-type, accepting 2x (0.75 to 25 mm²) stranded or 2x (0.25 to 2.5 mm²) solid wire. The control circuit terminals handle 2x (0.75 to 16 mm²) solid or stranded. That's enough cross-section for the full AC-1 and AC-3 current ratings without needing to parallel conductors. The minimum solid wire size of 0.25 mm² is fine for signal-level control wiring, and the 25 mm² stranded max covers the main power feed for the 22 kW motor circuit.
Coil and auxiliary ratings
The coil operates at 50 Hz and pulls 27 VA at 50 Hz rated value. Auxiliary contact ratings are given for several control voltages: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, 0.3 A at 220 V, 6 A at 230 V, and 3 A at 400 V. These cover most common PLC output and relay interface voltages. The arcing time is 10 to 15 ms, and the on-delay at AC is 7 to 20 ms — fast enough for typical sequence control.
Environmental and mounting
Operating temperature range is -25 to +40 °C, storage is -55 to +80 °C. Pollution degree 3 means it's rated for industrial environments with conductive dust or occasional condensation. Side-by-side mounting is allowed, so you can pack multiple contactors on a DIN rail without derating for heat buildup — useful when building a compact motor control center section.