The E3SAT31 is a PNP output photoelectric proximity sensor from the Omron E3S-A series, pre-wired with a red LED source. It detects up to 7 m with a 500 µs response — fast enough for package tracking and conveyor gap detection. Rated IP67, so it stands up to washdown environments. How many you need? I can source these.
Drop-in with E3SAT81
The E3SAT81 carries the same specs — PNP, 7 m, 500 µs, pre-wired, IP67, red LED. It's a direct functional substitute: same mounting hole pattern, same three-wire PNP wiring colors (brown, blue, black). If your BOM listed E3SAT81, the E3SAT31 fits without a panel change. We can quote either code.