The Siemens SIRIUS 3RH1122-1TB00-0KV0 is an auxiliary contactor — Size S00 frame, 45 mm wide, 57.5 mm tall, 72 mm deep. It's the signal-switching half of a contactor pair: 2 normally-open and 2 normally-closed instantaneous contacts, with a varistor built in for surge suppression across the coil. Rated for 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, and 1 A at 690 V — those are the thermal current ratings for the auxiliary contacts, so it handles control-circuit loads across common voltage levels without derating surprises. The contact reliability spec says one incorrect switching operation per 100 million operations at 17 V, 1 mA, which is the dry-circuit threshold that matters for PLC inputs and low-energy signal paths. Mounts via screw or snap-on onto a DIN rail — the +/-180° rotation on vertical surface and +/-22.5° tilt gives you real flexibility in a crowded panel. IP20 on the front means it's protected against finger contact, but not washdown; keep it inside the enclosure.
Sourcing and lifecycle
RoHS compliance date is 07/01/2006, so it meets the EU directive. No UL or CSA mark is listed in the spec record, but the SIRIUS family typically carries IEC/EN certifications for global panel builds — verify the specific approval for your jurisdiction against the datasheet.
Wire terminations
Terminal capacity accepts solid conductors: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), and 2x 4 mm². That's enough for daisy-chaining auxiliary circuits without piggyback terminals. Strip length and ferrule sizing follow standard practice for spring-cage or screw terminals — no special tooling needed.