The SICK WL8G-P2131 is a miniature photoelectric retro-reflective sensor from the W8G series, with a 3 m sensing distance and PNP output. It switches in 0.5 ms, which is fast enough for counting applications on a moderate-speed conveyor or detecting small parts at a pick-and-place station. The visible red LED makes alignment straightforward during commissioning — you see the spot on the reflector.
At 11 mm wide and 31 mm tall, this sensor fits into tight machine frames or multi-sensor arrays where space is the constraint. The M8 3-pin connector keeps wiring clean — no loose pigtail to manage inside a cable track. IP67 means it handles washdown and dust on a packaging line or in a wet machining cell without a secondary enclosure.
Output and switching logic
PNP output with light/dark ON selectable gives flexibility to match the PLC input card logic without an external inverter. The 100 mA load current drives a small relay or PLC input directly. Supply range is 10-30 VDC, so it works on standard 24 VDC control power with headroom for brownout conditions.