Railway-rated contactor relay, SIRIUS S00 frame
The Siemens 3RH2140-2XF40-0LA2 is a SIRIUS contactor relay designated for railway applications, built on the S00 size frame. It carries 4 normally open instantaneous contacts and is designed for screw and snap-on mounting onto 35 mm DIN rail, with a mounting position that allows ±180° rotation on a vertical surface and ±22.5° tilt forward/backward, plus standing or horizontal mounting — flexible for tight railway enclosures. Coil rated 72–125 VDC, with a holding current mean value of 7 mA and an inrush current peak of 1.1 A. The built-in varistor surge suppressor handles the arcing time of 10–15 ms and the DC operate time of 25–45 ms — no external snubber needed for standard inductive loads.
Mechanical integration and wiring
Dimensions: 73 mm deep, 45 mm wide, 70 mm high — fits the S00 footprint. Fastening is screw and snap-on onto 35 mm DIN rail; side-by-side mounting is permitted. Wiring accepts 2 x 0.5–4 mm² solid or stranded conductors. Clearance spacings: 10 mm upwards, 10 mm forwards, 10 mm downwards, 6 mm at the side. The varistor suppressor is integral, so no additional space needed for an external RC module.