Sensor in a 12.2 mm slice
The SICK WTB4SL-3P2261 is a miniature photoelectric proximity sensor from the W4SL-3 series, using a red laser for background-suppression detection. It senses objects between 25 mm and 300 mm, regardless of color or reflectivity, and switches a PNP output at up to 100 mA. The 500 µs response time suits fast-moving parts on a conveyor or pick-and-place station. With an M8 4-pin connector, it drops into a standard sensor cable without hardwiring.
The 300 mm maximum range is the reliable detection limit for a white 90% reflective target; darker surfaces reduce that distance, so the 25 mm minimum ensures close-range objects are still caught. Background suppression means the sensor ignores objects beyond the set switching distance — useful on a conveyor where you want to detect a product but not the belt or support structure behind it. The red laser (class 1) produces a small, visible spot for easy alignment. PNP output is common in North American control panels; sourcing current is 100 mA, enough to drive a PLC input directly or a small relay. IP66 and IP67 ratings mean the housing and optics withstand washdown and temporary submersion — suitable for food-and-bev lines or outdoor installations.
Deployment context
The 12.2 mm width and 41.8 mm height let this sensor fit into tight spaces on a machine frame or conveyor rail. The M8 4-pin connector mates with standard M8 cordsets; no panel wiring is needed. IP66/IP67 protection allows direct mounting in wet or washdown zones without an additional enclosure.