The Siemens 3RH1122-2VB40-ZX95 is a SIRIUS coupling relay designed for switching auxiliary circuits in control panels. Front-side protection is IP20, so it's intended for enclosed panel installation where personnel don't contact live parts.
The built-in diode surge suppressor handles the inductive kickback, so you don't need an external flyback diode across the coil — verify polarity matches the diode orientation before wiring. Contact ratings are given per voltage: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, 2 A at 500 V, and 1 A at 690 V. For a 24 VDC control circuit, the full 10 A is available; at higher AC voltages the current derates due to arc extinction limits. That's a dry-circuit rating — it will switch low-level signals from sensors or PLC outputs without needing a minimum wetting current.
The relay measures 45 mm wide, 60 mm high, and 73 mm deep. Shock resistance is 10g for 5 ms and 5g for 10 ms. The screw terminals accept solid or stranded conductors from 0.25 to 2.5 mm² (2 x 2.5 mm² per clamp).