The SICK WSE250-2R1531 is a through-beam photoelectric sensor from the W250-2 series, built for long-range presence detection up to 50 m between emitter and receiver. That 50 m reach means you can span a warehouse aisle, conveyor gap, or vehicle entry point with a single beam pair — no reflector needed, just clean line-of-sight alignment. Its relay output (1 changeover contact rated 3 A) switches loads directly — no interposing relay for most PLC inputs or small contactors. The 15 ms response time is fine for part-present or pallet-in-position checks, but too slow for counting fast-moving items on a high-speed line.
Switching logic and wiring
This sensor is Light-ON only — the relay energizes when the receiver sees the beam. That's a fixed behavior; there's no Dark-ON or teach-in option. If your application needs output on beam break (e.g., detecting a missing part), you wire the normally-closed contact of the changeover relay instead. Power range is 24–240 V AC/DC, which covers most industrial control voltages without a separate supply module. The 2 m cable termination is a fixed pigtail — no M12 connector, so factor in junction boxes or extension cables if the sensor sits far from the panel.
The 20 mm wide housing fits standard 20 mm slot-mount brackets common in the W250 family. Height is 60 mm, length 43.9 mm — compact enough for tight panel layouts or machine frames.