In Israel we have also these controller box to control the traffic lights. Several systems is computerized and there is detector volume that cause the traffic light system to skip road with no cars or to turn the traffic light red when the road is depleated of cars. I have even saw several traffic signal controller boxes that their electricity is backed up with generators when there is a power failure.
i hear the Electronics inside are senstive to the point where Climate control is installed in the cabninents...and ours dont seem to have Battery Backup.
The backup that i means but i don't described well is not only for the controller boxes, but also for the traffics lights themselves and is provided by diesel generators. So the entrie traffic lights system continue to work when there is a power failure. These generator is mainly on traffic lights systems on dangerous junctions or junctions where traffic jam may accur if the system will went out.
Just a few days ago.....in Laurel on Route 1....there was one traffic light set that had a stuck green....so they turned on the yellow flashers so what I saw was lit green and flashing yellow and the cops were there.....getting ready to direct traffic
Sometimes our Signals Malfunction and Flash Red for no Apparent Reason....sometimes during a Power Outage the Power is cut to the Controller..then when it comes back on the Signals are Flashing Red.