The Square D / Telemecanique XCKM102 is a general duty, compact limit switch from the Osiswitch line, built for position sensing on industrial machinery where a mechanical roller detects cam or part presence. It carries a 1NO-1NC contact block rated 240 VAC at 3 amperes and 250 VDC at 0.27 ampere — the AC rating handles pilot-duty control circuits on conveyors, packaging lines, and machine tools; the DC rating is lower because DC arcs are harder to extinguish, so keep that 0.27 A ceiling in mind if you're switching a DC solenoid or small brake coil.
This is a panel-mounted limit switch — the compact body mounts directly to machine frames or brackets via the two mounting holes in the switch body. The PG11 cable gland entry means you run the cable through a 11 mm threaded hole and tighten the gland for strain relief and ingress protection; no separate conduit box needed for most installations. Screw clamp terminals inside accept solid or stranded wire up to roughly 14 AWG — strip about 7 mm, torque to the manufacturer's spec (typically 0.5–0.6 Nm for this class). The 1NO-1NC contact configuration is the standard form C (SPDT) arrangement: one normally-open and one normally-closed set, sharing a common. Wire the NC side into the safety circuit for a fail-safe that opens on actuation; the NO side signals the PLC input. Both contacts are silver-alloy and snap-action, meaning the contact speed is independent of the plunger speed — no teasing or partial contact.