The Omron D4A1102N is a plug-in limit switch from the D4A series, configured as an SPDT momentary switch with a side roller arm plunger actuator (actuator not included, but a boot is supplied). It's built for environments that demand both ingress protection and washdown endurance: the body carries an IP67 rating and NEMA enclosure ratings of 1, 2, 3, 4X, 5, 6P, 12, and 13, meaning it can be installed in outdoor, wet, or dusty locations — including direct hose-down zones — without an additional enclosure. Contact ratings are 10 A at 250 VAC, and on DC: 6 A at 30 V, 10 A at 14 V, 0.8 A at 125 V, and 0.4 A at 250 V. The SPDT form gives a normally-open and normally-closed pair, so you can wire it for either break-before-make or complementary signaling. Screw terminals make field termination straightforward — no special crimp tool needed.
The aluminum body measures 1.73 in deep by 1.65 in wide by 2.97 in high, with a surface-mount pattern using two 0.2 in diameter holes spaced 59 mm vertically and 29 mm horizontally. Pretravel is 6°, overtravel is 75°, and total travel is 82° — the switch needs a full sweep to the hard stop, so verify your cam's angular throw against these numbers. The 3° differential travel means a small release angle before the contacts reset; useful for fast-cycling applications where you want a clean break without chatter. Operating temperature spans -40 °F to 212 °F, so it's at home in both cold storage and hot washdown areas. The maximum operating torque is 3.54 in-lb — a light cam or roller won't overpower the mechanism, but a heavy actuator arm might need a torque limiter. The switch is marked shock-resistant, which helps in high-vibration machinery like conveyors or presses.