Part identity and function
The Siemens 3RH1140-1AP00-ZX95 is a SIRIUS auxiliary contactor — a 4 NO (instantaneous) switching block designed to extend the control-circuit contacts on a motor starter or to build logic interlocking in a panel. It is built on the Size S00 contactor frame, which means it shares the 45 mm width and screw/snap-on mounting footprint with the S00 power contactor family.
What the ratings mean for fit
The 4 NO contacts are all instantaneous (no leading, lagging, delayed, or make-before-break variants), so this is a straight parallel set for standard control logic. Switching capacity is given per contact at several voltages: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, and 1 A at 690 V — these are the thermal current ratings at those AC voltages, so the contactor can handle the listed current at the stated voltage in a control circuit. The 6 kV rated surge voltage resistance means the contacts can withstand transient spikes common in industrial panels without welding or arcing over. Contact reliability is specified as one incorrect switching operation per 100 million operations at 17 V, 1 mA — this is the low-energy switching floor. If your PLC output card drives this contactor at 24 V and 10 mA, you are well above that threshold, so no dry-contact issues. The mechanical life is 30 million operating cycles typical. The IP20 protection on the front means it is finger-safe from the front but not sealed against dust or moisture — standard for a DIN-rail component inside a closed cabinet. Pollution degree 3 confirms it is rated for conductive pollution environments typical of industrial control panels.
Mounting and integration
Fastening is by screw or snap-on mounting onto a DIN rail. The mounting position is flexible: +/-180° rotation on a vertical surface, and can be tilted forward/backward by +/-22.5° on a vertical surface. This matters when you are squeezing it into a tight gland-plate layout or a rotating sub-panel. The 45 mm width is the standard S00 slice — three of these fit in a 135 mm wide section, which helps fill-factor planning. Wire cross-sections accepted: 2x (0.5...1.5 mm²), 2x (0.75...2.5 mm²), and 2x 4 mm² solid. That covers most control-circuit wiring from 20 AWG to 12 AWG. The 72 mm depth and 57.5 mm height are standard for the S00 frame, so it will fit existing S00 backplates and gland plates without interference.
Lifecycle and sourcing posture
For BOM freeze or compliance documentation: the substance prohibitance date is 07/01/2006, which aligns with RoHS compliance. The operating temperature range is -25 to +60 °C; storage and transport range is -55 to +80 °C. Shock resistance is 10g / 5 ms and 5g / 10 ms, which covers most industrial vibration environments.