The Siemens 3RK1911-4AB16 is an ECOFAST selective block designed for selective switching-off in a maintenance switch function. This is a SIRIUS-series accessory that sits between a contactor and the load, allowing an operator to isolate a specific branch of a machine for safe maintenance while other sections remain powered.
The 16 A rated current is the continuous current the block can carry in its intended duty. For a maintenance switch function, this means it can handle the full-load current of a motor or resistive load up to that ampacity without overheating. The M12 feedback contact gives a discrete signal back to the PLC or safety relay confirming the block is in the open (isolated) position — a standard requirement for lockout/tagout verification in a safety circuit.
Deployment context
The M12 feedback connector is a 4- or 5-pin industry-standard round connector, common in sensor/actuator wiring on automated lines — no special tooling needed beyond a standard M12 cordset.