LED Lighting shut down when a voltage sag occurs


Senior Member
Hello, I work for a utility company, and I have had a small handful of customers over the years tell me that their LED lighting (in commercial and industrial settings) will shut down randomly and will not come back on until they open the breaker and close it back. Some report a blink of the lights, which makes me think a short duration voltage sag occurred. Monitoring with a power quality monitor always shows good voltage. Voltage sags occur everywhere from time to time, and most customers do not seem to have this issue. Does anyone have any insight into what is causing this to happen? I am sure there are some electronics in the light that get "confused" when the voltage sag occurs, and then they have to be rebooted in order to reset. But I am looking for a better explanation. :p

Sag no light

Sag no light

This is just a guess, but there might some form of protective circuit in the LED driver (power supply) that locks out the fixture until it is repowered, now in normal street lighting the photocell would do that, but in a residential or commercial setting that would have to be done by the end user.