High Pressure Sodium 70 Watt(12 posts)
Sorry you were in the hospital and hope you are recovering OK.
I took a good guess at the correct answer because my plant maintenance folks had the problem constantly when the seasons changed and the leaves fell off the nearby trees close to the parking lots.
Regular old photocell detectors on Street and Parking Lot overhead lights to detect darkness.
You remember the kind.
When they fail, they fail ON so lights remain ON even during day light.
Have to sometime rotate them a bit because of reflections or sun angle during season changes.
Also, sensitivity was sometimes controlled by small shade over photocell opening.
New styles can be IR, but assumed old detector in this problem.
Kind of like these newer ones.
These new ones have time delay but no spec provided.
Everything has changed now.
Even in our small town, Utility Co. reads the electric meters with a hand held IR device from a truck.
Was Engr. Mgr. with Landis & Gyr Plant when we started developing this type of utility meter.
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