Integrator note — SIRIUS S2 power contactor
The Siemens 3RT1036-3KJ84-0LA0 is a SIRIUS power contactor in size S2, rated for 30 kW at 500 V in AC-3 duty — that is the motor-switching rating that governs the real load on a conveyor, pump, or fan circuit. AC-4 at 400 V carries 41 A for reversing or plugging applications where the contactor sees inrush on every cycle. The 10 million mechanical operations typical life means this part is specified for high-cycle production lines, not occasional start-stop. Mounts via screw and snap-on onto 35 mm DIN rail per EN 50022. Side-by-side mounting is permitted, which keeps panel density high. Screw-type terminals on the main current circuit accept solid 2x (0.25... 2.5 mm²) or stranded 2x (0.75... 25 mm²) — the larger stranded range covers the power feed for the 30 kW load. Pollution degree 3 means it is rated for industrial atmospheres with conductive contamination.