The Omron D4C1702 is a metallic-body limit switch from the D4C series, built for wet or washdown environments. Its IP67 rating means the housing and the cable entry keep out dust and survive temporary immersion — a common spec for food-and-bev or car-wash stations where a standard limit switch would fail in weeks. The roller plunger actuator (stainless steel roller, 0.47 in diameter, 0.17 in width) sits on top and operates with a pretravel of 0.07 in and total travel of 0.19 in, so it catches a cam or a part edge with a short, positive stroke. The SPDT contact block switches 5 A at 250 V AC or 4 A at 30 V DC — enough for a PLC input or a small contactor coil, but not for direct motor starting. The switch comes with a 16.4 ft SJT(O) cable attached, so you land the wires in a junction box rather than opening the switch body. That saves time on a ladder or a conveyor frame. The body is aluminum, surface-mount with two holes, and carries NEMA 3, 4, and 13 ratings — meaning it handles rain, hose-down, and oil spray. The boot-sealed actuator is not included (no boot), so if the plunger sits in a direct-spray zone, plan to shield it or add a boot separately.
The D4C1702 is at a mature lifecycle stage. It is not promoted for new designs but remains available through distribution channels with no last-time-buy notice.
The AC contact rating of 5 A at 250 V is the resistive (general-use) load. For inductive loads, derate or add a snubber; the DC rating of 4 A at 30 V indicates the arc-quenching limit.