what kind of Batteries are in there?...Lithium?...do the Batteries charge when Mains Current is Avalible?

We have a few traffic light systems in MD that appears to have them....also I was told the controllers even have air conditioning/heaters in them!

Supposedly the Electronics inside are Sensitive Enough that a Climate Control is needed!

Odd because ours don`t have heat or AC.

I read something about a cabinet heater on the MTO website but I haven't heard of them being used here. I also haven't seen a spec for a AC unit before too.

Question to US guys:
What is in the US law about non working signal lights?
I know, it first go to the red/amber flashing mode, what (i guessed it) mean "Stop" from the red side, but what if the lights go out completely? It became "All-way stop" crossing? As i have never seen there any signs on normally light controlled crossings...

Here (in Europe) it go to amber flashing or some shut down completely, what both mean exactly the same: "Crossing is not controlled by lights", so the driver should observe signs (or right-hand rule, if there are no signs).

The LED lamp based signs have aircons, they need it to cool the win98 based pc inside it and the LED drivers. The traffic signals use a 286 processor in most, it has no need for cooling aside from it's heatsink

yeah it says Desktops can Run as Signal Controllers with Proper Software Installed....i dont know how much the Program is but a PC would be less expensive than a Dedicated Controller.

I doubt anybody is using regular PC here...
The desktop PC would never have the reliability of at least industrial controller.
But it is true, then lot of controllers are in fact PC compatible machines, only build with way better quality and so are way more expensive...

Traffic controls are a dedicated controller, most likely an Intel device. The signs are more likely to use a standard PC inside, as they are not designed to give service for multi decade periods without failure, as the traffic signals are.

The streetlighting controllers in Israel on Haifa, Nesher and Jerusalem cities are also remote controlled by PC computers with a software called Wizcon.
Also in traffic light, in Israel, when there is a power interuption, if the batteries of the controller become empty the traffic lights are goes out completely. And if they are flashing orange, this means that there is a problem with the system.

@Medved, in the US a blacked out signal is the same as a 4 way stop. All cars are required to come to a complete stop and cross when safe. the car to the right has the right of way. Any pedestrians crossing have the right of way.

Also often when blacked out signal happens, sometimes police gets involved for traffic directing...

That doesn't happen here often Seagull! Most times the drivers take their chances that a taxi will not careen though the intersection, lights working or not. Top 100 owing fines are mostly taxis, not politically expedient to get the drunken b@st@rds to cough up.

I've seen people in my area go right through red lights all the time, most people are always in a rush and they don't give a sh@t if they hit or kill someone.

@ Form109, the batteries are lead-acid gel cells, deep cycle. They charge when mains pwer is on, and discharge during an outage.
>> This cabinet only has a fan to circulate air, the battery box has provisions for mat heaters in cold areas, to keep the batteries from freezing.

Does the Battery Charging System work like that of a Warning Siren?...cause on those the Batteries Charge for a Period of Time...then Charging Ceases for a while,after the While is Up the System checks the Batteries then charges them again.

I noticed in Florida, in the event of a power outage the traffic signals simply go out. Drivers dont seem to treat them as stop signs so a policeman is required to direct traffic.

Around here, it varies! If it goes out completely...police gets involved......There may be some systems that have battery packs.....but some don't....

I recall the traffic lights here simply going out when they lose power and drivers are expected to treat them as a 4 way stop but most of the busier streets need police involvement to direct traffic.