The Siemens 3RH2122-1KB40 is a SIRIUS coupling relay for auxiliary circuit switching: 24 V DC coil with integrated suppressor diode, 2 normally-open instantaneous contacts, and a rated mechanical life of 30 million cycles. Housed in the S00 contactor frame, it measures 73 mm deep by 45 mm wide and mounts via screw or snap-on onto 35 mm DIN rail.
Coil & Contact Ratings
Coil draws 2.8 W at 24 V DC. The rated operational current per voltage is 10 A, 10 A, 3 A, and 1 A.
Mounting & Clearance
Fastening via screw clamp or snap-on to 35 mm DIN rail. Mounting position allows ±180° rotation on a vertical surface and ±22.5° tilt forward/backward. Required clearances for proper arcing and cooling: 10 mm upward and forward, 10 mm downward, 6 mm to the side.