The Siemens 3RH1122-1AB00-ZX95 is a SIRIUS auxiliary contactor in frame size S00 — the compact 45 mm wide footprint that snaps onto DIN rail or screws directly to a mounting plate. It carries two normally open and two normally closed instantaneous contacts (2 NO + 2 NC), no leading or lagging delay, no make-before-break. That contact complement is the standard choice for signal interlocking, feedback loops, and extending the auxiliary contact count on a main contactor or motor starter without adding a second device.
The contact ratings vary by voltage because the load current a set of contacts can safely interrupt drops as voltage climbs. At 24 V the contacts are rated for 10 A — that is the maximum resistive or general-use load at control voltage. At 230 V the rating is 6 A, at 400 V it drops to 3 A, and at 690 V it is 1 A. These are the thermal current ratings (Ith) that govern continuous carry and making/breaking under normal load. The surge voltage resistance is 6 kV, so the contact gap is sized for 400/690 V industrial environments without needing additional suppression on the contacts themselves.
Mechanical endurance and mounting flexibility
Shock resistance is 10g at 5 ms and 5g at 10 ms, which is sufficient for most industrial machinery but not for extreme mobile or naval applications.
Termination and wire sizing
The screw terminals accept solid conductors: 2x 0.5 to 1.5 mm², 2x 0.75 to 2.5 mm², or 2x 4 mm². That covers standard control wiring from 20 AWG up to roughly 12 AWG. The twin-entry allows looping through without a separate terminal block, common in daisy-chained control circuits.