PGA-LS10 Photoelectric Point Sensor with Sensor Check 
This sensor has a detection area of a 2-m (7 ft) half-sphere for arcs of 3 kA or more.  
A built-in LED enables the PGR-8800 to verify the function of the light sensor, wiring, and electronics. If the sensor does not detect the sensor-check LED, a sensor-fail alarm will occur -- the ONLINE output will change state and the ONLINE LED will begin to short flash.
The sensor includes 10 m (33 ft) of shielded three-wire electrical cable which can easily be shortened or extended to a maximum of 50 m (164 ft). Use Belden 85240 or equivalent cable (wire colors may vary).