The SICK WTB9L-3P2461 is a W9-series photoelectric proximity sensor with background suppression, using a visible red laser for a 300 mm sensing range. It switches a PNP output at 100 mA, with a 500 µs response time, making it suited for precise object detection on high-speed packaging or assembly lines. The laser spot gives a defined detection zone from 25 mm out to 300 mm, with background suppression meaning it ignores objects beyond that cutoff — useful for sensing on conveyors where the belt or a backstop must not trigger the sensor. Rated IP66, IP67, and IP69K, the housing withstands high-pressure washdown and temporary submersion, so it can be mounted directly on a filling line or in a washdown zone without a protective enclosure.
The 300 mm sensing distance with background suppression is the headline spec: it detects a target at up to 300 mm while ignoring reflective surfaces behind that point. The 25 mm minimum sensing distance means the target must be at least 25 mm from the sensor face for reliable detection. The 500 µs response time (ON and OFF) means the sensor can detect objects passing at high line speeds — roughly 300 m/min for a 2.5 mm target — without missing a pulse. Operating voltage is 10–30 VDC, and the PNP output sinks up to 100 mA, enough to drive a PLC input directly or a small relay. The M12 4-pin connector is standard for industrial sensors; the pinout matches most M12 male cordsets. The 12.2 mm wide housing fits into tight mounting rails or alongside other sensors in a multi-sensor bank. Ambient temperature range is -10 °C to +50 °C.
No official successor or replacement part number has been issued; this is the active design-in part for the W9 laser background-suppression family.