Siemens 3RH2131-1BB40 Auxiliary Contactor Relay 24 V DC Coil

The Siemens 3RH2131-1BB40 is a SIRIUS 3RH2 auxiliary contactor relay designed for reliable control-circuit switching and signal amplification in industrial automation and panel applications. It features three normally open (3 NO) and one normally closed (1 NC) contact configuration with a 24 V DC coil, making it suitable for standard control logic and interlocking tasks. Built on an S00 frame size, this compact relay mounts easily on DIN-rail or panel setups and uses screw-type terminals for secure electrical connections. With good insulation (up to ~690 V) and robust mechanical design, the 3RH2131-1BB40 delivers dependable switching performance in machine control, signal distribution and automation environments.