Phased Out — Successor Identified
The Siemens SIRIUS 3RH1911-1FA11-ZX95 is a phased-out product. The manufacturer lists the successor as the SIRIUS 3RH2 series. For new designs or BOM replacements, the 3RH2 is the direct drop-in intended by the factory.
What It Is and Where It Fits
This is an auxiliary switch block from the Siemens SIRIUS family, designed for use with contactor relays and power contactors of size S00. It snaps onto the contactor without tools — no additional hardware needed. The block provides one normally open and one normally closed contact, wired via screw-type terminals. It accepts solid or stranded conductors: 2x (0.5... 1.5 mm²) or 2x (0.75... 2.5 mm²) with core-end processing.
Key Ratings and What They Mean for Fit
Rated for a maximum of 10 A across the auxiliary contacts. The actual current-carrying capacity depends on the voltage: at 24 V it carries 6 A, at 230 V it carries 6 A, and at 400 V it drops to 3 A. For DC switching, the ratings are lower — 10 A at 24 V DC, 4.7 A at 60 V DC, and 0.5 A at 440 V DC. The AC-15 rating at 690 V is 1 A — this is the switching capacity under inductive load conditions typical for contactor coils and solenoid valves. The surge voltage resistance is 6 kV, and the insulation voltage at pollution degree 3 is 690 V. Mechanical service life is 10 million switching cycles typical. Contact reliability is specified as one faulty switching operation per 100 million operations at 17 V and 5 mA — this matters for low-signal PLC inputs where oxide films on dry contacts can cause intermittent faults.
Mounting and Integration
Snap-on mounting onto the contactor — no DIN rail required for the block itself. The dimensions are compact: 36.5 mm wide, 37.5 mm high, and 41.5 mm deep. IP20 on the front face, so it is protected against finger contact but not washdown; suitable for enclosed control panels. Operating temperature range is -25 to +60 °C; storage range is -55 to +80 °C. The part carries the note "with 3RH1" — this indicates compatibility with the 3RH1 contactor relay series specifically, though it also fits S00 power contactors.