The Siemens 3RH1140-1AR10 is a SIRIUS auxiliary contactor in size S00, carrying four normally-open instantaneous contacts rated for 10 A in AC-12 duty. That AC-12 rating — resistive loads at unity power factor — is the figure that governs its use in control circuits feeding PLC outputs, relay coils, and indicator lamps. The 4 NO configuration means it adds four isolated signal paths without introducing any delayed or make-before-break switching, so it slots into standard interlocking and feedback circuits where timing must stay deterministic.
At 45 mm wide, 57.5 mm tall, and 72 mm deep, this contactor occupies a single modular DIN-rail pitch — standard for a size S00 block.
Beyond the headline 10 A AC-12 rating, the contacts carry defined currents at other common control voltages: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, and 1 A at 690 V.
Terminals accept solid conductors in three size ranges: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), and 2x 4 mm². For AWG, the equivalent is 2x (20 to 16), 2x (18 to 14), and 1x 12. The degree of pollution is rated 3, meaning the contactor is designed for environments with conductive or dry non-conductive pollution — typical of most industrial control panels not in clean-room conditions.