The Siemens SIRIUS 3RT1036-1XF40-0LA2 is a Size S2 power contactor with a 110 V rated coil, designed for screw and snap-on mounting onto 35 mm standard mounting rail per DIN EN 50022. It carries a 30 kW motor rating at 500 V in AC-3 duty and 11.4 kW at 690 V, making it a fit for medium-horsepower motor switching in control panels.
The AC-3 rating of 30 kW at 500 V defines the contactor's ability to switch three-phase induction motors on and off under full load — that's the number to match against your motor nameplate. At 690 V the same duty drops to 11.4 kW, reflecting the higher arc energy at elevated voltage. For AC-2 duty (slip-ring motor starting), the rating is 22 kW at 400 V, which covers wound-rotor applications where the contactor handles starting current without full-load interruption. That's enough for frequent start-stop cycles on conveyors or pumps without wearing out the mechanism prematurely. Arcing time sits at 10 to 15 ms, and DC operating time is 20 to 25 ms — fast enough for most sequencing requirements. The auxiliary contact block handles 10 A at 24 V, 6 A at 230 V, and 3 A at 400 V — sufficient for signaling back to a PLC or for interlocking with other contactors in a motor control center. The coil pick-up threshold is 0.7 of rated voltage, and drop-out is at 1.25 of rated, ensuring reliable operation even with slight voltage sags on the control transformer.
Side-by-side mounting is allowed, saving rail space when grouping multiple contactors in a motor control center. Clearance requirements are 10 mm upwards, downwards, forwards, and to the side — tight enough for dense panel layouts. Main circuit terminals are screw-type, accepting 2x (0.75 to 25 mm²) stranded or 2x (0.75 to 16 mm²) solid/stranded wire. The maximum cross-section at AC-1 rated current is 16 mm². Auxiliary terminals accept 2x (0.5 to 1.5 mm²) solid, 2x (0.75 to 2.5 mm²) solid, or max 2x (0.75 to 4 mm²) — standard for control wiring. Strip length and torque values follow the terminal marking on the contactor.