During my travels today I noticed at an intersection that the caltrans people were readying a set of traffic lights and a controller box to be moved back several feet to accomidate the expansion of the road there. I made a comment to one of the electricians there asking if they were fixing the y2k. They told me no that they were just moving the lights back. Then I asked them if they were going to fixing the y2k. They told me that they hope to have a fix for it in the next couple of months. I left at that point,then I returned later and talked to the electrical supervisor who was a nice man. We talked at lenght and he showed me a little about how it operated. From what I was able to see, the traffic system can fallback to a fixed time routine, but I noticed that it uses a two digit date code in it's programing. The controller for stop lights looks to me like a modified 16 bit PLC with it's timing routine instructions burned in by the vendor. While the traffic engineer can select from a number of tod traffic patterns,there is no room on these controllers to handle year field expansion. Another potential problem is that some traffic signals are linked to a central mainframe controller station in some cities. Then there is the problem of not a lot of qualified traffic engineers to handle the major disruptions or to do the vast quantities of up grades that will be required to bring all of the traffic signals into compience in time. We will see a lot of traffic signals with a flashing red light,providing we have power for the first few months in to y2k expect it. y2k aware mike going into the trenches to find out the truth from the workers in the field.

-- y2k aware mike (y2k aware mike@ conservation.com), May 20, 1999

Answers

You say; some traffic signals are linked to a central mainframe controller station in some cities.

Those are controlled for specific reasons, not daily use. Such as setting an area to all red lights around a fire station to allow the fire trucks and aid cars to get out of a congested area. Otherwise look at each corner that has a traffic light, you will find a box at each one. Just one of those things we "see" everyday but do not regester.

-- Cherri (sams@brigadoon.com), May 20, 1999.

You are referring to the Opticom systems. Those aren't in universal service in every city.

Most of the systems dont have RTC's. The older versions have seven day timers (they know the hour and the day of the week and not much else). Supposedly Safetran's newest version with internal RTC's is y2k compliant. (software upgrade).

In addition to customized timing in every version, (new or old) there is an internal standard timing set as a fall back if the memory is corrupted. No other operator or mainframe supervision is required (JUST 120VAC).

There are two seriuos problems for traffic signals. One is their complete dependence on 120VAC power. Unless your city has upgraded to LED lights, each signal array has about three 100w light bulbs. Each intersection has eight or more bulbs on 24 hours a day. There is NO BACKUP power for the bulbs.

The second serious problem is for large cities. Many times the traffic is so heavy that the signal timing has been optimized for rush hour. If the controllers switch to their default settings this will cause traffic jams. The battery backup at each signal control box will only hold up for around 24 hours. Older batteries may fail to recharge.

Y2k problems at the mainframe (well actually more likely a PC server) may cause problems, especially if telephone and power problems also hit at the same time. Our server can check the status of each box and restore the soft settings several times a day if necessary. In our city, only about half the signals are hooked to the server. The other half are stand alone. In fact a lof of our town has one way streets and stop signs. (does yours?)

In short, the level of problems can be a complex function of what happens, it doesnt require that the signal controllers have y2k problems internally. For instance, within the last three years there have been SEVERAL incidents nearby where a simple traffic problem (3 car accident, or a ladder blocking one freeway lane, or a bomb threat under one freeway bridge) that have crippled ALL major surface streets and freeways. A trip to the Lucky's that normally takes 5 to 10 minutes turns into a 90 minute creeping "linear parking lot".

The signals were all working. The power and phones were all on. The local media (radio/tv) were late on the story. It doesn't take y2k

Safetran McCain

-- hunchback (quasimodo@belltower.com), May 20, 1999.

Lest we forget, or don't know, when ones comes to an intersection with a signal device that is not functioning, that intersection becomes a four way stop.

Now, if we could only program the drivers to understand this the problems will not be as great.

After the hurricane in '92 we had several accidents because of the ignorance of some drivers at these intersections. Other accidents at actual four way stops [read signs] were common as well because the signs were gone.

Why is it that these drivers, presummably local and familiar with the roads, forgot where the signs were? One accident I saw, involved a fatality when one car failed to stop at a known four way stop. The intersection had been posted as such for a good ten years, until the 'cane removed the signs.

Geez! When it rains here, it seems everyone with bald tires and broken wipers gets on the road! Rain washes away the common sense of the drivers. Headlights? What are they? Turn signals? What are they?

And they wonder why we have road rage!

I would like to see public service announcements on television reminding people what the rules of the road are, and even pointing out standard features of cars, like lights, wipers, turn signals, etc.

That is something the government can do! But, alas, they probably won't....

-- J (jart5@bellsouth.net), May 20, 1999.

Don't exaggerate the problem, and please on't assume "all" cities are going to respond the same way.

Example, Marietta, GA has already fixed the problem, Orlando (last I heard) needed some fixes (updates) form their vender, and was concerned about getting the changes installed in time. (Their option was to reset (if needed) their mainframe to 1972 - assuming the mainframe op system will accept that date...) One city in VA has also remediated and finished testing.

So if power is up in each area, these would be okay.

Others may fail, may reset to defaults, or may "fail" to an invalid day-of-week but run okay until reset to "Sunday", or may just be "blinking red" - who knows what will happen if not remediated? For example, Atlanta is not now apparently even going to be able to get to its street lights programs; they still are trying to get 911 and city systems operable at all.

Anyway - yes, you are right, some may fail in some areas. But not all, not all in all areas by any means.

-- Robert A. Cook, PE (Kennesaw, GA) (cook.r@csaatl.com), May 20, 1999.

I expect to see lots of flashing red lights in January. The Jacksonville area I drive through Mon-Fri right now is synchronized for rush hour traffic. It's 15 miles of the worst 6 lane road I have ever seen (and that includes Atlanta). There are stoplights every 50 to 100 feet. If it is flashing red or out completely when I get there, I'm turning around and going home. After all, whenever there is an accident on this road it takes an hour to go that 12 miles. I don't even want to think about how long it will take in that circumstance. My total trip right now is 40 miles, but that 15 in the middle can make it or break it.

-- DJ (reality@check.com), May 20, 1999.

I would be thrilled to see flashing red lights January 1. My fear is not seeing any lights at all.

-- Doug (douglasjohnson@prodigy.net), May 20, 1999.