The Siemens 3RH7122-1AV00 is a SIRIUS contactor relay in frame size S00, carrying a 22 E contact configuration — two normally-open and two normally-closed auxiliary contacts. It is a switching element for control circuits, not a main power contactor; the contacts are rated for the auxiliary circuit loads listed below. The AC coil draws 27 VA pickup, 5.4 VA holding, with a power factor of 0.8 on pickup and 0.27 on hold.
At 24 V AC the rated value is 6 A; at 110 V it drops to 1 A; at 220 V it is 0.3 A. At 230 V and 400 V the rating returns to 6 A, and at 690 V it is 1 A. The 0.3 A at 220 V and 1 A at 690 V reflect the reduced switching capacity at those voltages. The contacts are also qualified for PLC control reliability at 17 V, 5 mA — meaning they can switch low-energy signals without contact oxidation issues.
At 45 mm wide and 72 mm deep, it occupies a single S00 footprint on the rail. Screw-type terminals accept 2x 0.5–1.5 mm², 2x 0.75–2.5 mm², or 2x 4 mm² solid/stranded conductors.