Auxiliary switch block for SIRIUS contactor relays
The Siemens 3RH2911-1GA22-ZW97 is a front-mounted auxiliary switch block for the SIRIUS contactor relay family, delivering 2 normally-open and 2 normally-closed contacts in a physically coded housing that mates only with 3RH2140 and 3RH2440 contactor relays per EN 50011. Rated at 10 A, it carries 10 A at 24 V and derates to 6 A at 230 V or 250 V, with AC-15 switching capability at 690 V rated 1 A — so it handles pilot-duty loads like PLC inputs and relay coils across a 24 V to 690 V control range.
Contact reliability and switching life
Insulation voltage is 690 V at pollution degree 3, surge voltage resistance 6 kV, and front protection IP20 — adequate for enclosed control panels where the switch is behind a door.
Screw-type terminals accept 2x (0.5 to 1.5 mm²) and 2x (0.75 to 2.5 mm²) with core end processing, or AWG 2x (20–16) and 2x (18–14). The switch block includes two instantaneous contacts (the 2 NO + 2 NC set) with no leading or lagging contact — all four poles switch simultaneously, so it suits straightforward status feedback or interlocking without timing tricks.