Part identity and role
The Siemens 3RH2131-1AB00-ZX95 is a SIRIUS auxiliary contactor in frame size S00, carrying three normally-open instantaneous contacts and a 24 V 50/60 Hz coil. It's the signal-switching companion to a power contactor — used to pick up status feedback, interlock sequences, or extend the I/O count on a motor starter without adding a separate relay bank.
The S00 footprint — 45 mm wide, 57.5 mm tall, 73 mm deep — fits standard panel layouts; the ±180° rotation on a vertical surface and ±22.5° tilt forward/backward give flexibility for tight gland-plate or door-mounted arrangements.
Three NO contacts rated across the voltage spectrum: 10 A at 24 V AC, 10 A at 230 V AC, 3 A at 400 V AC, 1 A at 690 V AC. DC switching is lower — 4.7 A at 60 V, 0.5 A at 440 V, 0.26 A at 600 V. These are the numbers that govern whether the contactor holds up in a high-cycle packaging line or a valve manifold that sees continuous shuttling.
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. The screw-clamp design is standard for the SIRIUS range — no special tooling needed, but a PZ1 or PZ2 bit is typical for the terminal screws.