The Omron D4NL2FFAB4S is a safety-door lock switch from the D4NL series, designed to interlock access doors on machinery where a key-actuated mechanical lock is required. It carries a 1NO/4NC contact configuration — one normally-open channel for the monitoring circuit and four normally-closed channels that break on door opening, giving you redundant safety isolation. Rated IP67, the switch body and actuator withstand washdown environments, so it fits on food-processing lines or in wet-area machine guarding where water ingress would kill a standard limit switch.
Mechanical life is rated at 1 million cycles, electrical life at 500,000 cycles — that's typical for a solenoid-driven safety switch and gives a solid MTBF for a high-cycle guarding application.
Mounting dimensions: 88.5 mm wide, 95 mm tall, 35.5 mm deep. The screw terminals accept standard control wiring; the key actuator is field-reversible for four head directions, so you can orient the switch to match the door swing without ordering a separate actuator variant. The 4NC contacts let you wire a dual-channel safety circuit (two contacts in series per channel) while still having one NC contact available for a feedback loop or a second guard position — common in Category 3 or 4 safety systems per ISO 13849.