SIRIUS S2 contactor with extended operating range
The Siemens 3RT2035-3XJ44-0LA2 is a SIRIUS S2-size contactor designed with an extended operating range — meaning the coil holds in reliably even when the control voltage dips below nominal, a real-world advantage on long cable runs or weak control transformers. Rated 40 A at 480 V in AC-3 duty, it handles motor switching for pumps, fans, and conveyors up to that full-load current without derating at the standard 40 °C ambient. The 41 A rating at 600 V AC-3 means it also covers 480 V applications with headroom, and the 7.5 hp at 230 V gives a quick horsepower cross-check for North American panel builders.
Spring terminals and panel fit
Spring-type terminals on the coil and main contacts — no screw torque to verify, no vibration loosening over time. The 55 mm width and 114 mm height fit standard S2 panel spacing; depth is 178 mm including arc chamber.
Coil and auxiliary specs
DC coil rated 72 V with a 0.7 initial pickup multiplier — the extended-range design means it pulls in at about 50 V and stays sealed down to roughly 22 V, giving a wide brownout tolerance. No built-in auxiliary switch — add a separate SIRIUS auxiliary contact block if you need feedback or status. AC-4 switching rate is 300 cycles per hour maximum. Arcing time runs 10 to 20 ms, and the drop-out delay is 30 to 55 ms on DC.
Environmental range and storage
Operates from -40 to +70 °C ambient — suitable for unheated enclosures in northern climates or near process heat. The full-scale value of 1.25 on the coil means it can handle 125 % of rated voltage continuously without overheating the magnet wire.