The Siemens 3RT1035-1BA40 is a SIRIUS S2 power contactor, rated for switching motor loads up to 22 kW at 500 V in AC-3 duty, or 18.5 kW at 400 V in AC-2 duty.
AC-3 switching at 1 000 operations per hour is the real-world motor-starting rhythm — conveyor duty, pump cycling, fan starts. The AC-4 rating of 35 A at 400 V covers inching or plugging applications where the contactor breaks full-load current under stalled-rotor conditions. Pollution degree 3 means it's built for the conductive-dust and humidity environment inside a typical industrial enclosure, not a clean room. The screw-type main terminals accept stranded wire up to 2x 25 mm², and solid up to 2x 4 mm². That's enough for the 16 mm² minimum at 40 °C ambient — so you aren't fighting undersized lugs on a warm panel day. Auxiliary contact wiring uses the smaller 0.5-to-1.5 mm² solid range typical for control circuits. The arcing time of 10-15 ms and DC dropout time of 20-25 ms are what you'd expect for this frame size — no surprises when timing interlocking with a downstream starter.