The Square D XCKJ161 is a heavy-duty limit switch from the Osiswitch line, built for industrial position sensing in wet, dusty, or washdown environments. Its NEMA 1/2/4/12 and IP66 enclosure means it seals out hose-directed water and airborne dust — suitable for food-processing lines, machine tools, and outdoor conveyor systems where a standard limit switch would fail from ingress. Contact rating is 240 VAC 10 Ampere and 250 VDC 0.27 Ampere (SPDT, snap-action). The AC figure governs motor-control circuits and solenoid loads; the DC figure is derated significantly because DC arcs are harder to extinguish — at 250 VDC the switch is limited to 0.27 A, so it will not handle a typical 24 VDC sensor load above that current. For DC control circuits, verify the load current stays under the 0.27 A limit at the applied voltage. The top rod plunger actuator (spring return, snap action) provides a direct mechanical interface for cam- or slide-actuated positions. Pretravel is 0.08 inch, differential travel 0.035 inch, total travel 0.24 inch — the narrow differential means the switch changes state with minimal overtravel, useful for precise position detection on indexing tables or press slides.
Construction and integration
Body is Zamak zinc alloy, corrosion-resistant and dimensionally stable under vibration. Connection is via a PG13.5 cable gland with screw-clamp terminals — the gland accepts standard 1/2-inch trade-size conduit or cable, and the screw clamps handle solid or stranded wire up to about 14 AWG. No plug-in base; wiring is direct to the switch body, so replacement requires rewiring at the terminal block. Operating temperature range is -13 to 158 °F (-25 to 70 °C), covering most indoor and sheltered outdoor installations. The switch carries UL and CSA approval, plus compliance with EN/IEC 60204-1 (machine safety) and EN/IEC 60947-5-1 (control circuit devices). These standards are the baseline for industrial control panels in North America and Europe.