The D4NL2AFAB4 is a safety-door lock switch from Omron's D4NL series, built for interlocking guard doors where the machine must not open until the hazardous motion has stopped. The 2NO / 2NC contact configuration gives you two normally-open safety channels and two normally-closed monitoring channels — the NO pair feeds the safety relay or controller, the NC pair signals door position back to the PLC. That's a standard dual-channel arrangement for Category 3 / PL d per EN ISO 13849-1. Switching capacity is 3 A at 240 V AC and 270 mA at 250 V DC. The AC figure covers most control-circuit loads (contactors, relays, solenoid valves) within a 24–240 VAC panel. The DC rating is lower because DC arcs are harder to extinguish — 270 mA at 250 VDC is typical for small indicator lamps or PLC digital inputs; don't plan to switch a DC solenoid or brake directly without checking inrush against the 270 mA continuous limit. IP67 means the switch body and the actuator entry are sealed against dust ingress and temporary immersion — suitable for washdown zones in food processing, packaging lines, or outdoor conveyor transfers. The screw terminals accept ferruled stranded or solid wire; strip length per the manufacturer's recommendation is 7–8 mm to avoid exposed conductor outside the cage.
Mounting and mechanical notes
The switch measures 88.5 mm wide, 95 mm tall, and 35.5 mm deep — a compact footprint that fits standard 40 mm profile framing. The head can be oriented in four directions (top, bottom, left, right) relative to the actuator entry, which simplifies alignment on hinged or sliding guards. Mechanical lock type means the key (actuator) stays trapped when the solenoid is de-energized; the door cannot open until the control circuit releases the lock. Rated mechanical life is 1 million cycles, electrical life at rated load is 500,000 cycles. Those numbers assume the switching frequency and load stay within the datasheet's derating curves — inductive loads or higher inrush will reduce electrical life proportionally.