The Square D XCKD2910N12 is a compact limit switch from the Osiswitch family, built for severe-duty environments. It carries a 240 VAC 10 A contact rating (250 VDC 0.27 A) with a 2NC snap-action configuration — the NC contacts give you a fail-safe circuit that opens on actuation, which is what you want in a guard-door or position-confirm loop where a lost signal should stop the machine. The ZAMAK metal body and NEMA 1/2/4/6/12/13 plus IP66/IP67 enclosure mean this switch survives washdown, hose-down, and temporary submersion — common on food, beverage, or outdoor conveyor lines. The top push rod plunger actuator gives a direct, short-stroke mechanical trip; pretravel is 1.8 mm with 0.9 mm differential, so it responds to a positive stop without over-travel slop.
Wiring and integration
Connection is via a 1/2-inch NPT conduit entry with screw-clamp terminals inside. That's a standard knockout size for North American metallic conduit or liquid-tight fittings.