A summary of New York City's signal history

[M30]

Over the years, in the city of New York, signals and signal controllers have improved in many ways to guide motorists safely throughout the city.


In the beginning of the 20th century, early devices of traffic signals were installed at major intersections in New York City. They were normally controlled manually by police officers. It wasn't until the early 1920s or so, that two-section traffic signals first began to appear on the streets of the city of New York. They were manufactured by Ruleta, and they had appeared as fixed four-way, two-section (red and green) traffic signal.

The original sequence was rather interesting in its own way. When a Ruleta traffic signal changed from green to red, there was a "dark out period" that lasted for only a handful of seconds. Then, afterward, the red indication would be displayed. It wasn't until the early 1950s that a new sequence was introduced. The new display was the red indication overlapping the green indication. In other words, both were displayed at the same time. This basically represented a yellow indication to drivers, and this told drivers to come to full stop. Afterward, the green indication would go dark.

In the early 1950s or so, three-section traffic signals first began to appear on the streets of New York City. And, in 1955, pedestrian signals were first introduced.

During that decade, the 1950s, of course, mast-arm poles with guy wire installations were also introduced in the city of New York. They date back to as far as 1954.

The 1960s saw the installation of mast-arm poles and three-section traffic signals, for that two-section traffic signals were slowly dwindling. Two-section traffic signals survived until around 2005 or so in New York City. As of present day, they are extinct.

Since everything was incandescent in New York City for a long time, L.E.D. module inserts were introduced in 1999. The next year, 2000, the city of New York began the conversion from incandescent light bulbs to L.E.D. module inserts. It took at least four years to complete this conversion.


As far as signal controllers are concerned, New York City had used electro-mechanical signal controllers for a very long time. It wasn't until 2006 or so that the city first began to used computerized signal controllers. Since then, they have replaced numerous electro-mechanical signal controllers. N.Y.C.D.O.T.'s goal is to have every signalized intersection in the city of New York controlled by a computerized signal controller.

[Jace the Gull]

From what I saw myself, going to NYC every time, I noticed they first converted the red ones to LED keeping yellow and green incandescent, then green was next after about a year or two and finally yellow....

But I know some of the traffic light systems in NYC still has the old controllers, there's one near my grandmas house that makes a lot of clicking noises when signals changes....I have a video of it somewhere!

[M30]

Though this thread is fairly old, I did not know until now that someone posted a comment quite a while back!

In any case, in regards to the L.E.D. inserts, yes, N.Y.C.D.O.T. first began to use red L.E.D. inserts as far back as 1998. At the time, these inserts were developed by CooperLED/AtLite Inc., and numerous inserts were provided to New York City and tested in solely the borough of Queens for the first time. CooperLED/AtLite Inc. developed the green L.E.D. insert in 2000 and redesigned its red L.E.D. insert. The green and second generation red L.E.D. inserts were installed by N.Y.C.D.O.T. throughout the rest of the boroughs.

Today, in Queens, many of the original red L.E.D. inserts are still in service, and they are the oldest still in use.

[joe_347V]

Looks like NYC started using LED very early on. Over here LED didn't appear until around 2000 or 2001 at the earliest. Most cities didn't start retrofitting until 2004 or so. The last of the incandescent signals were removed only in early 2013.


Just wondering about the New York signals, I heard that the NYCDOT stuck with glass lenses and reflectors all the way until LED came out. Is it because glass gives a more intense beam?

[M30]

Looks like NYC started using LED very early on. Over here LED didn't appear until around 2000 or 2001 at the earliest. Most cities didn't start retrofitting until 2004 or so. The last of the incandescent signals were removed only in early 2013.


Just wondering about the New York signals, I heard that the NYCDOT stuck with glass lenses and reflectors all the way until LED came out. Is it because glass gives a more intense beam?

All traffic signals in New York City used to use glass reflectors and lenses, in which was a standard from the days of red and green traffic signals until the mid 2000s or so. As far as an exact reason is concerned, I am unsure at this time; however, I would imagine your reason sounds plausible.

After N.Y.C.D.O.T. successfully retro-fitted its existing vehicular signals with red and green L.E.D. inserts in 2004, amber signal indications were still incandescent at the time. This is also true for those that were newly installed at intersections. Though the standard was altered several years ago, and new traffic signals must use all three L.E.D. signal indications. Incandescent amber signal indications still in use in older heads are not affected by this; however, once a light bulb dies, the whole set-up is replaced by a L.E.D. insert.