What it is and where it lands
The Siemens SIRIUS 3RH1140-2BB40-ZW96 is a size S00 auxiliary contactor with a 24 V DC coil, four normally-open instantaneous contacts, and IP20 protection on the front. It is rated for a surge voltage of 6 kV and carries a pollution degree of 3, meaning it is designed for industrial control panels where contact multiplication or signal routing is needed alongside a main contactor or motor starter.
Mounting and integration
Mounts via screw or snap-on onto a DIN rail; the 45 mm width and 73 mm depth fit the standard S00 footprint. The mounting position allows +/-180° rotation on a vertical surface and +/-22.5° tilt forward/backward, which gives flexibility in tight enclosures. Terminal capacity accepts 2x (0.25 to 2.5 mm²) solid or 2x 24–14 AWG stranded — use ferrules for stranded wire to avoid whiskers under the screw clamp.
Contact ratings and coil draw
The coil pulls 3.2 W DC both on pickup and hold — no economizer circuit, so the thermal load on the DC supply is constant. Contact ratings are given per voltage: 10 A at 24 V, 1 A at 110 V, 0.27 A at 220 V, 6 A at 230 V, 3 A at 400 V, 2 A at 500 V, and 1 A at 690 V. These are thermal current ratings for the auxiliary contacts; for inductive loads, derate per the switching frequency and load type. Contact reliability is specified as one incorrect switching operation per 100 million operations at 17 V, 1 mA — suitable for low-level signal switching in PLC or safety circuits.