The WTB4FP-31311120 is a SICK W4F miniature photoelectric proximity sensor with background suppression. Its 220 mm max sensing distance (4 mm min) means it detects objects reliably against a background at that range — the background suppression cuts false triggers from reflective surfaces behind the target. The push-pull output (100 mA load) works with both sinking and sourcing PLC inputs, so it drops into most control circuits without a conversion interface. Response time is 500 µs, fast enough for counting on moderate-speed conveyors or detecting parts at typical packaging-line rates. The visible red PinPoint LED makes alignment visible during commissioning — you see the spot on the target rather than guessing. IP66 and IP67 mean the sensor body handles washdown and temporary submersion. In a food-and-beverage plant or outdoor conveyor, that keeps it running through hose-down cleaning cycles without potting or extra shrouding.
Width is 16 mm, height 40.1 mm, length 12.1 mm. The M8 3-pin connector mates to standard M8 cordsets. Operating voltage range is 10-30 VDC. Temperature range is -40 to +60 °C.