What it is and what it does
The Siemens 3RH2131-1AU60 is a SIRIUS auxiliary contactor in frame size S00, with 3 normally open instantaneous contacts. It's the switching block for signaling and control circuits in a motor starter or contactor assembly — not the main power path, but the logic side that tells the PLC or HMI what the main contacts are doing. Rated for 10 A at 230 V AC and 10 A at 24 V DC, it handles typical control voltages across a plant floor. The switching capacity drops predictably at higher voltages — 3 A at 400 V AC, 1.2 A at 220 V DC — so the buyer matches the voltage column to their control transformer tap. Surge voltage resistance is rated at 6 kV, which covers most industrial panel transients without external suppression.
Mounting and integration
Mounts via screw or snap-on onto 35 mm standard DIN rail. The S00 frame footprint is 45 mm wide by 73 mm deep by 57.5 mm tall — a compact block that fits in a crowded panel without stealing space from the main contactor. Mounting position is flexible: ±180° rotation on a vertical surface, plus ±22.5° tilt forward/backward, so it adapts to whatever orientation the enclosure layout demands. Clearance distances are specified: 10 mm upwards, 10 mm forwards, 10 mm downwards, 6 mm at the sides. These are the minimum air gaps to maintain rated insulation and heat dissipation — an integrator laying out a dense row of S00 devices should respect those numbers to avoid derating.
Wiring and termination
Terminals accept 2 x (0.5 to 1.5 mm²), 2 x (0.75 to 2.5 mm²), or 2 x 4 mm² solid or stranded copper, plus the AWG equivalents (2 x 20-16, 2 x 18-14, 2 x 12). That covers the range from signal-level wiring up to the heavier gauge needed for longer control runs. Screw-clamp termination is standard for this class — no spring-cage option on this variant.
Environmental and compliance
Operating temperature range is -25 to +60 °C, storage from -55 to +80 °C. Relative humidity minimum is 10%, pollution degree 3 (conductive pollution or dry non-conductive pollution that becomes conductive due to condensation — typical for industrial control panels not in sealed clean rooms). The substance prohibition date of 10/01/2009 confirms RoHS compliance for the European market.