The Siemens SIRIUS 3SF1214-1KC05-1BA1 is a mechanical safety switch with positive-opening contacts — the kind you spec when a guard door has to physically force the NC contacts open, no spring failure allowed. Two safety-related NC contacts and zero NO auxiliaries mean it's a pure safety channel; if you need a status feedback signal to the PLC, you'll add an external auxiliary block or a separate position sensor. The 24 V LED gives a quick visual on contact state at the switch body — useful during commissioning or when a line-down tech is walking the cabinet with a flashlight.
IP66/IP67 and the washdown reality
Rated IP66/IP67 with a metal enclosure and cathodic dip coating — this switch survives hose-down and temporary submersion. That's the spec you want on a packaging line, a food-grade conveyor, or any zone where washdown chemicals hit the guard interlocks. The M12 plug with the AS-Interface pinout keeps the connection sealed; no field-wiring gland to leak.
AS-Interface integration note
This is an AS-Interface basic switch with a fixed M12 plug. The slave profile is 0.B.F, and the ID1 code is F hex, variable 0...F. Pin 1 = ASI+, Pin 3 = ASI-; pins 2 and 4 are unassigned. The switch communicates its state over the AS-i bus — no separate I/O wiring back to the safety PLC. The 24 V LED is powered from the AS-i bus voltage, not a separate supply.