What it is and where it fits
The 3RH2911-1XA40-0MA0-Z W98: This is an auxiliary switch block that snaps onto the front of Siemens 3RT2 contactors and 3RH2 contactor relays. It gives you four normally-open (NO) auxiliary contacts — labeled 53/54, 63/64, 73/74, and 83/84 — each with screw terminals for field wiring. The 4 NO arrangement is a clean way to add status feedback or interlocking without a separate terminal block.
Deployment context
Snaps onto the contactor or relay front — no DIN rail space consumed. The screw terminals accept standard control wiring; torque to the contactor's terminal spec. Four NO contacts give you enough for a feedback loop to a PLC plus a separate run-status lamp, all from one add-on block. On a panel build, this keeps auxiliary wiring off the main power terminals.