What causes gradual lighting up of street illumination on long streets?
mr_fish04 asked:
When they light up street illumination in cities like New York, it seems to be progressive and not all the lights are on at the same time. It seems like a “flow of power” turning them on gradually as it progresses through the wires. But I am quite convinced that it is just for effect or rather to protect the power network and not because electric current works like that. I think that physicaly when you connect power supply to a wire all the lights connected to that wire light up at the same time no matter how long the wire is. Is there any related material online describing this problematics of lighting up big cities?
When they light up street illumination in cities like New York, it seems to be progressive and not all the lights are on at the same time. It seems like a “flow of power” turning them on gradually as it progresses through the wires. But I am quite convinced that it is just for effect or rather to protect the power network and not because electric current works like that. I think that physicaly when you connect power supply to a wire all the lights connected to that wire light up at the same time no matter how long the wire is. Is there any related material online describing this problematics of lighting up big cities?
Hi friend
2 reasons can cause this:
1. heating: the streets lighting turn off when they warm up
2. the photocell that light a group of them on is in a trouble or its area is not dark for any reason [who]
remove the first two words of your question and put it in a search engine. [who]
The answer is pretty simple. Sometimes an electrical contractor will install a photocell to control an entire electrical circuit. In this situation, all lighting will switch on and off at precisely the same time. In the scenario you are talking about, the electrical contractor with the lowest bid got the job. Instead of installing a photocell for the entire circuit, he went the cheaper route and bought light fixtures, each with its own integral photocell installed from the factory. In this case, each light switches on and off independently from the other fixtures on the same circuit. As shadowing progresses down a street, the lights will start coming on, one after another, and it appears that it is for “effect”. You can rest assured that no city would spend money for street lighting effects. [who]