The SICK WTB4S-3P2232V is a miniature photoelectric proximity sensor from the W4S-3 series, using background suppression to detect objects at a fixed distance independent of color or reflectivity. The 120 mm maximum sensing range with a 4 mm minimum means it reliably detects objects from nearly touching the lens out to 120 mm — useful for small-part presence on conveyors or fill-level detection where the background is farther than the target. Background suppression cuts false triggers from shiny or dark backgrounds behind the target. The PinPoint LED visible red light produces a small, intense spot that makes alignment visible to the naked eye — no laser safety paperwork needed, but still precise enough for 500 µs response time on fast-moving parts. That 500 µs response means it can catch objects moving past at several meters per second, suitable for high-speed packaging or sorting lines. Rated IP66, IP67, IP68, and IP69K — the IP69K rating specifically means it withstands high-pressure, high-temperature washdown cycles common in food-and-beverage and pharmaceutical lines. The sensor body and optics survive caustic wash chemicals at 80 °C and 80–100 bar, so it can be mounted directly in washdown zones without a protective housing.
The 15.25 mm wide, 44.9 mm tall, 22.2 mm deep housing fits into tight machine frames where every millimeter counts — think end-of-arm tooling, small transfer stations, or multi-sensor arrays on a 20 mm grid. The M8 4-pin connector keeps wiring clean; no cable gland to torque, just plug and go. PNP output is the standard for most PLC input cards — sourcing 100 mA at 10–30 VDC drives small contactors, solenoid valves, or indicator lights directly. Light/Dark ON switching is selectable via the teach-in or wiring — common for both presence (light ON) and absence (dark ON) detection. The wide operating temperature range from -30 °C to +70 °C covers cold storage and hot washdown zones without derating.