The Siemens 3RH2140-2BW40 is a SIRIUS auxiliary contactor, size S00, with four normally open instantaneous contacts and a 48 VDC coil. It is designed for screw and snap-on mounting onto 35 mm DIN rail, making it a straightforward panel fit for control circuits needing extra contact sets. Rated switching capacity varies by voltage: 10 A at 24 V and 230 V, 3 A at 110 V and 400 V, 2 A at 500 V, 1.2 A at 220 V, 1 A at 690 V, 0.5 A at 440 V, and 0.26 A at 600 V. These are the AC ratings that govern contact life in motor control or signal switching — match the voltage on your line to the right column. The coil draws 4 W closing and holding power, a steady DC load that stays constant once picked. Ambient operating range is -25 to +60 °C, storage from -55 to +80 °C. Pollution degree 3 means it's rated for industrial environments with conductive contamination — standard for panel-mount gear.
Sourcing & Lifecycle
RoHS compliance date is 10/01/2009. No UL or CSA listing is stated in the available data, but the SIRIUS platform typically carries those for industrial control panels — verify with your local Siemens support if a specific agency mark is required for your jurisdiction.
Mounting & Integration
Mounts on 35 mm DIN rail via screw and snap-on. The S00 footprint is compact: 45 mm wide, 70 mm tall, 73 mm deep. Clearances for arc and cooling: 10 mm upward, 10 mm forward, 10 mm downward, 6 mm at the side. Mounting position allows ±180° rotation on a vertical surface and ±22.5° tilt forward/backward. Terminals accept 2x 0.5 to 4 mm² solid or stranded wire. Mechanical life is 30 million operations typical. Maximum switching frequency is 10,000 cycles per hour AC; DC arcing time runs 7 to 13 ms.