The Siemens SIRIUS 3RH1140-2AD00 is a size S00 auxiliary contactor with four normally-open instantaneous contacts, rated 10 A in AC-12 duty at 400 V. It is designed to switch control-circuit loads — pilot lights, PLC inputs, contactor coils — rather than motor power. The 10 A AC-12 rating means it handles resistive and lightly inductive control loads up to that current, which covers most 24 VDC and 230 VAC control circuits in a standard panel. Mounting is screw or snap-on onto DIN rail, with the S00 footprint matching the same panel cutout as the 3RT2 contactor family.
The four NO contacts are rated across the full control-voltage range: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, and 1 A at 690 V. These are AC-12 values — the relevant duty class for resistive control loads. For DC switching, the 24 V rating holds at 10 A, dropping to 1 A at 110 V and 0.27 A at 220 V. The contacts are instantaneous only — no delayed, lagging, or make-before-break options on this variant.
Environmental limits and installation conditions
The unit withstands shock at 10g / 5 ms and 5g / 10 ms, adequate for panel-mounted equipment in industrial machinery. Side clearance is 0 mm — devices can be mounted flush side-by-side without derating. Front face protection is IP20, so the contactor is touch-safe once installed in a closed panel. Wire termination accepts 2x solid conductors from 0.25 to 2.5 mm², covering standard control wiring. The screw terminals are compatible with ferruled ends for consistent connection quality.