They got a bad rap up here in the North where we get snow. Blowing snow would often coat the lenses of traffic signals. Incandescents generated enough heat to just melt the snow, but LED replacement lamps would not and people could no longer see some of the signals. They now have thermostat-controlled heaters to solve the problem, but it made many cities gunshy.
People that write specs for government are quite conservative (not politically, necessarily, but more slow to change). That and the early issues with them is plenty to keep some cities specifying incandescent bulbs.
The only time I’ve seen that happen is when they used the full-circle hoods. Almost every one I’ve seen has a cutout at the bottom to prevent snow from accumulating.
They probably have heaters too though. I am not a traffic signal engineer.
They got a bad rap up here in the North where we get snow. Blowing snow would often coat the lenses of traffic signals. Incandescents generated enough heat to just melt the snow, but LED replacement lamps would not and people could no longer see some of the signals. They now have thermostat-controlled heaters to solve the problem, but it made many cities gunshy.
Technology Connections has a whole video on the danger of, “but sometimes” pertaining to those lights. It’s a great watch if you’re interested
+1 for that channel.
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People that write specs for government are quite conservative (not politically, necessarily, but more slow to change). That and the early issues with them is plenty to keep some cities specifying incandescent bulbs.
The only time I’ve seen that happen is when they used the full-circle hoods. Almost every one I’ve seen has a cutout at the bottom to prevent snow from accumulating.
They probably have heaters too though. I am not a traffic signal engineer.
Snow gets sticky. It will stick. It has been a problem, but easily fixed with heaters.
https://abcnews.go.com/GMA/ConsumerNews/led-traffic-lights-unusual-potentially-deadly-winter-problem/story?id=9506449