How it works-Everything that has to do with the light is controlled by the controller box as you can see in the picture above. The picture i have above is the system for traffic lights in bigger cities that is why in the picture above that there is a camera. Traffic lights in small towns such as elkin as sit on a timer. Instead of being controlled by a camera or a wireless radio.
Safe Fail feature- The safe fail feature on the traffic light is that if the controller box goes out all lights connected will flash red to keep people from wrecking and it has a computer system inside the controller box that notifies the technicians soon as the system goes down. However the fail safe feature can fail if there is a power outage or there is something wrong within the light its-self.