The Siemens 3RH1131-2BB40-0TK0 is a SIRIUS auxiliary contactor in the S00 frame size, carrying a 24 V DC coil that draws 3.2 W during both closing and holding — no economizer circuit needed, so the coil dissipation stays constant regardless of how long it's energized. That fixed 3.2 W load matters when you're sizing a 24 V DC control transformer or a SELV power supply for a panel with a dozen such contactors; the thermal budget adds up linearly. Rated for 10 A in AC-12 duty (resistive loads at 24 V), the contact set also carries defined currents at higher voltages: 6 A at 230 V, 3 A at 400 V, 2 A at 500 V, and 1 A at 690 V. These are not derating curves you interpolate — each is a tested rating for that specific voltage. For a 400 V control circuit common in European motor control centers, the 3 A figure governs; don't assume the 10 A AC-12 rating holds at 400 V.
Mounting and integration
Mounts via screw or snap-on onto a DIN rail — the S00 footprint is shared across the SIRIUS contactor family. The mounting position allows ±180° rotation on a vertical surface and ±22.5° tilt forward or backward. Dimensions are 45 mm wide, 60 mm high, and 73 mm deep. The width is the critical panel-pitch dimension: at 45 mm, it occupies one standard 45 mm module position on a DIN rail, matching the pitch of many miniature circuit breakers and terminal blocks in the same enclosure. Terminals accept solid conductors of 2x 0.25 to 2.5 mm² — two conductors per clamp, which is useful for daisy-chaining the control supply through multiple contactors without additional junction points. The IP20 front protection means it's safe from finger contact in a closed panel but not for exposed mounting.
Environmental and compliance
Rated for pollution degree 3, with surge voltage resistance of 6 kV. Operating temperature range is -25 to +60 °C, with storage and transport extending from -55 to +80 °C. The storage limit governs handling — the part can sit in a cold warehouse or hot container without damage, but the operating limit is the one that matters for the panel ambient. Shock resistance is 10g for 5 ms and 5g for 10 ms, adequate for most industrial machinery but not for continuous high-vibration environments like a crusher or mill without additional damping. RoHS compliance dated to July 1, 2006, covering the original EU RoHS directive. Contact reliability is specified as one incorrect switching operation per 100 million cycles at 17 V and 1 mA — a dry-circuit rating that matters when switching low-level signals from PLC inputs or sensors, where oxide films on silver contacts can cause intermittent opens.