The Siemens 3RH1344-1AN20-ZX95 is a SIRIUS auxiliary contactor, size S00, carrying 4 normally-open instantaneous contacts and no delayed, leading, lagging, or make-before-break switching contacts. It is designed to switch control signals and auxiliary loads in motor starter and contactor assemblies, not main power.
Mechanical endurance is rated at 10,000,000 typical switching operations, with contact reliability specified as one incorrect switching operation per 100 million at 17 V, 1 mA — a low-level signal rating that matters for PLC inputs and electronic loads. Thermal current at 24 V is 10 A; at 230 V it drops to 6 A, and at 690 V to 1 A. These are the AC switching limits for the auxiliary contacts under the rated voltage. Shock resistance is 10g / 5 ms and 5g / 10 ms, sufficient for normal machinery vibration but not extreme shock loads.
No official successor has been announced, and no direct replacement is needed — the 3RH1344-1AN20-ZX95 is the active variant for its contact configuration. The -ZX95 suffix indicates a special version; verify the exact order code against your BOM to ensure the contact arrangement (4 NO, no NC) matches your schematic.
Solid conductor cross-sections accepted: 2x (0.5... 1.5 mm²), 2x (0.75... 2.5 mm²), and 2x 4 mm². This covers standard control wiring from signal-level to moderate power auxiliary circuits. No auxiliary switch extension is available on this variant.