What this part is and what it fits
The Siemens 3RH2911-2HA31-Z W96 is a front-mounted auxiliary switch block delivering 3 normally-open and 1 normally-closed contact paths. It's built specifically for the 3RT2 contactor series and the 3RH2 contactor relay series — same mounting footprint, same spring-loaded terminal interface. The spring-cage terminals accept solid or ferruled stranded conductors, which means no screw-torque checks during panel build; just strip, insert, and the cage holds.
Contact arrangement and wiring
The contact configuration is laid out as three NO (normally-open) and one NC (normally-closed) path. The description notes the current path sequence as 1 NC, 1 NO, 1 NO, 1 NO — so the NC occupies the first position in the terminal row. When wiring, you'll want to confirm which terminal pair corresponds to the NC before landing your safety-circuit loop; the NO contacts are the remaining three.