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Traffic signal

Started by Tom89t, January 14, 2012, 01:01:45 AM

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bcroadguy

Quote from: jakeroot on May 10, 2018, 10:06:53 PM
Quote from: bcroadguy on May 10, 2018, 06:47:22 PM
Quote from: jakeroot on May 09, 2018, 04:01:02 PM
Quote from: bcroadguy on May 09, 2018, 05:49:53 AM
Quote from: jakeroot on May 09, 2018, 12:28:53 AM
Two-section pedestrian heads are still commonly installed in various parts of British Columbia. They have been phased out in Washington, though.

And weirdly, some areas have switched from 16 inch pedestrian signals back to two-section signals in recent years.

Yeah, I'm not quite sure what the MOT is doing. Some new projects have the standard single-section pedestrian heads, whereas some will have two sections. None seem to be a newer style than another. They're both installed with regularity.

MOT only ever installs 12 inch pedestrian signals. For new signals at least, they'll only add a second section if there's going to be a countdown timer. Many cities (Surrey, Langley, Victoria, Vancouver etc..) install 16 inch signals, while others (Burnaby Coquitlam, Nanaimo etc...) are like the MOT and use 12 inch signals. It all depends on whichever agency is installing them's preference.

I believe Vancouver installs single-section heads which also include countdown timers, correct? I can't remember what other cities do. At the 99/16 Ave interchange, the MOT used two-section heads despite the availability of single-section pedestrian heads with countdown timers. That's what I find most interesting. I was not aware that any municipality was still installing ped heads without countdown timers.

They do! All the other cities in the first list in my previous comment do as well. As far as I know, only the MOT and Richmond don't always use countdown timers. Here's a brand new 12 inch pedestrian signal in Richmond without countdown timers: https://www.google.ca/maps/@49.1774636,-123.1243457,3a,45.3y,15.24h,97.96t/data=!3m7!1e1!3m5!1skqOlZqyAKaVca4T0bh09_Q!2e0!5s20120501T000000!7i13312!8i6656.


TBKS1

Hartshorne, Oklahoma. I took these yesterday.



^^ This signal was broken, unfortunately.

I take pictures of road signs, that's about it.

General rule of thumb: Just stay in the "Traffic Control" section of the forum and you'll be fine.

traffic light guy

Quote from: TBKS1 on May 11, 2018, 04:34:59 PM
Hartshorne, Oklahoma. I took these yesterday.



^^ This signal was broken, unfortunately.



The first one may be a McCain, the second one might be an 8" Peek

TBKS1

Quote from: traffic light guy on May 11, 2018, 05:18:03 PM
Quote from: TBKS1 on May 11, 2018, 04:34:59 PM
Hartshorne, Oklahoma. I took these yesterday.



^^ This signal was broken, unfortunately.



The first one may be a McCain, the second one might be an 8" Peek

Thanks for telling me what the models are!
I take pictures of road signs, that's about it.

General rule of thumb: Just stay in the "Traffic Control" section of the forum and you'll be fine.

freebrickproductions

Hard to tell, but they both look to be 8 inch McCains. Doesn't sound like the town really takes good care of them...
It's all fun & games until someone summons Cthulhu and brings about the end of the world.

I also collect traffic lights, road signs, fans, and railroad crossing equipment.

(They/Them)

TBKS1

Quote from: freebrickproductions on May 11, 2018, 07:32:25 PM
Hard to tell, but they both look to be 8 inch McCains. Doesn't sound like the town really takes good care of them...

I don't think they do either. It's pretty hard to see the green color on the signal, and as I mentioned above, the first signal is broken and needs to be replaced pretty badly.
I take pictures of road signs, that's about it.

General rule of thumb: Just stay in the "Traffic Control" section of the forum and you'll be fine.

traffic light guy

Not even that old either, I believe those signals date to the mid-90s.

Michael

This video showed up in YouTube's suggestions earlier (I don't know why since I haven't been watching any road related videos), and I just watched it:


It was quite informative.  I've never seen heated LED lenses before.  I also agree with the point that he makes about the right green arrow delay.  It's annoying to have a green ball go to a red ball, then get an arrow.  The only intersection I can think of this happening to me at is here.

paulthemapguy

Lmao I know the exact intersection where he went out to take pictures.

LEDs are sooooooooo much better than incandescent bulbs, though I am nostalgic for the incandescent bulbs' appearance.
The buildup of snow on traffic signal visors is very very rare.  It requires a lot of wind to accompany the snowfall.  But visors in his (and my) home state of Illinois have the bottoms cut out anyway, so the snow build up only ever happens if the wind is blowing side-to side.  In the rare occurrences when I've seen snow build up on the lenses, it would be either the left or right half of the lens that is covered; never really the bottom half.
Avatar is the last interesting highway I clinched.
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TM Clinches https://bit.ly/2UwRs4O

National collection status: 361/425. Only 64 route markers remain

SignBridge

Snow buildup is a more serious problem where I live on Long Island because our county traffic agency mostly uses partial visors which allow more snow to accumulate on the lenses.

MNHighwayMan

Quote from: Michael on May 14, 2018, 07:56:03 PM
I also agree with the point that he makes about the right green arrow delay.  It's annoying to have a green ball go to a red ball, then get an arrow.

I don't, because this means that the signal never has an all-red phase, where the intersection should be completely clear of vehicles from all directions.

jakeroot

Quote from: Michael on May 14, 2018, 07:56:03 PM
I also agree with the point that he makes about the right green arrow delay.  It's annoying to have a green ball go to a red ball, then get an arrow.

The green arrow can't come on while the oncoming left turn has a green or yellow orb. This would give the impression to right turning traffic that no other traffic might conflict with them, when, in fact, left turning traffic will be completing their left turn on yellow/red. Basically, on a yellow, all straight/right turning traffic must slow and stop to allow left turning traffic to go.

on_wisconsin

#1637
WisDOT's NW division is finally getting in the signal per-lane game. Taken at WIS 25/ N. Broadway St. and Ceder Falls Rd. in Menomonie:

Looking Northbound:




Southbound:



"Speed does not kill, suddenly becoming stationary... that's what gets you" - Jeremy Clarkson

jakeroot

Wisconsin has very good signal placement overall, so it surprises me that a far-right mast mounted signal isn't included. For many states, that's the only extra signal DOTs include.

MNHighwayMan

The only thing I don't like about that setup is the side-by-side signal heads in the median. I would much rather see the ball indication head mounted on the right mast and leave only the left arrows in the median.

Michael

Quote from: jakeroot on May 14, 2018, 09:57:11 PM
Quote from: Michael on May 14, 2018, 07:56:03 PM
I also agree with the point that he makes about the right green arrow delay.  It's annoying to have a green ball go to a red ball, then get an arrow.

The green arrow can't come on while the oncoming left turn has a green or yellow orb. This would give the impression to right turning traffic that no other traffic might conflict with them, when, in fact, left turning traffic will be completing their left turn on yellow/red. Basically, on a yellow, all straight/right turning traffic must slow and stop to allow left turning traffic to go.

In this case, there wouldn't be a left turn conflict since the oncoming left turn is protected only, and I can only recall seeing it lead only.  The green ending I'm referring to is straight through for east and west.  The next phase is either left turns from the right and left, or left/through from the right.  Would there still be an issue since there are no left turning cars from the oncoming direction?  The only issue I can think of is if someone jumps the red light before it turns green going straight across from the left.

traffic light guy

The three orb signals being mounted alongside the turn signals is actually pretty creative.

jakeroot

Quote from: Michael on May 16, 2018, 07:16:06 PM
Quote from: jakeroot on May 14, 2018, 09:57:11 PM
Quote from: Michael on May 14, 2018, 07:56:03 PM
I also agree with the point that he makes about the right green arrow delay.  It's annoying to have a green ball go to a red ball, then get an arrow.

The green arrow can't come on while the oncoming left turn has a green or yellow orb. This would give the impression to right turning traffic that no other traffic might conflict with them, when, in fact, left turning traffic will be completing their left turn on yellow/red. Basically, on a yellow, all straight/right turning traffic must slow and stop to allow left turning traffic to go.

In this case, there wouldn't be a left turn conflict since the oncoming left turn is protected only, and I can only recall seeing it lead only.  The green ending I'm referring to is straight through for east and west.  The next phase is either left turns from the right and left, or left/through from the right.  Would there still be an issue since there are no left turning cars from the oncoming direction?  The only issue I can think of is if someone jumps the red light before it turns green going straight across from the left.

The intersection in the video appeared to have pro/per phasing for all approaches. Several frames showed two overhead 5-section towers, which are used in Illinois when the left and right turns have protected phases (but not fully-protected operation). A green arrow coming on during a permissive phase might confuse drivers into thinking their movement is occuring while protected, when they actually have to stop and yield to those completing their left turn at the end of the cycle (common in Illinois).

If the intersection was fully protected, right turn green arrows could be used much more often, because the right turns would in fact be protected (as long as the pedestrian walk sign was not on, and the oncoming left turn had a red arrow).

There is an intersection near me in Tacoma, WA (Waller @ Pioneer), where the right turn onto Waller has a green right arrow that burns for more than 90% of the time. Because Waller is split-phased at that intersection, and the other approach to Pioneer has virtually no one approaching it ever, the only time the right green arrow ever turns off is when the oncoming left turn has a green arrow. I was initially curious why a yield on green signal was not used, but with the constantly burning green arrow giving the impression to right-turning traffic that their movement is fully protected, you could not use a permissive signal for the oncoming left turn. I'm sure such an operation has been permitted in the past, but to the best of my knowledge, a combination of a green orb and a green arrow for opposite approaches is not allowed.

Quote from: traffic light guy on May 16, 2018, 09:26:24 PM
The three orb signals being mounted alongside the turn signals is actually pretty creative.

I like it as well. Very Australian/Kiwi.

SignBridge

Pretty good configuration in those Wisconsin photos, but I wonder how often those median post-mounted heads get knocked down....... California had a lot of those years ago but they phased them out in favor of far-left corner heads.

Michael

Quote from: jakeroot on May 16, 2018, 09:49:36 PM
If the intersection was fully protected, right turn green arrows could be used much more often, because the right turns would in fact be protected (as long as the pedestrian walk sign was not on, and the oncoming left turn had a red arrow).

I was thinking of the intersection I posted a link to when I made my initial statement, and all left turns are protected only, so that explains my confusion!

jakeroot

#1645
Quote from: SignBridge on May 16, 2018, 09:50:17 PM
Pretty good configuration in those Wisconsin photos, but I wonder how often those median post-mounted heads get knocked down....... California had a lot of those years ago but they phased them out in favor of far-left corner heads.

I don't think California did a very good job placing its signals. Many jurisdictions around the world, including several here in North America, utilize median mounted signals without issue. What California and Nevada never did very well was placing them back from the intersection. If they are placed too close, they will get struck by wide vehicles turning left. British Columbia generally places protected left turns at least a couple of meters back from the crosswalk line.

roadfro

Quote from: jakeroot on May 16, 2018, 10:34:47 PM
Quote from: SignBridge on May 16, 2018, 09:50:17 PM
Pretty good configuration in those Wisconsin photos, but I wonder how often those median post-mounted heads get knocked down....... California had a lot of those years ago but they phased them out in favor of far-left corner heads.

I don't think California did a very good job placing its signals. Many jurisdictions around the world, including several here in North America, utilize median mounted signals without issue. What California and Nevada never did very well was placing them back from the intersection. If they are placed too close, they will get struck by wide vehicles turning left. British Columbia generally places protected left turns at least a couple of meters back from the crosswalk line.

Nevada was never really big on median signals (or at least, not to my knowledge). But you're right in that some of the ones I can think of were on narrow medians and right near the nose of the median... Current practice for nearly all jurisdictions is to just put left turn signals overhead.

There are three locations in Nevada I can think of with post-mounted signals in the median, two in Las Vegas and one in Sparks. In all cases, the posts are located on medians that are at least a traffic lane wide–although one Vegas location still puts the posts pretty close to the median nose.
Roadfro - AARoads Pacific Southwest moderator since 2010, Nevada roadgeek since 1983.

jakeroot

Quote from: roadfro on May 18, 2018, 10:39:21 PM
Quote from: jakeroot on May 16, 2018, 10:34:47 PM
Quote from: SignBridge on May 16, 2018, 09:50:17 PM
Pretty good configuration in those Wisconsin photos, but I wonder how often those median post-mounted heads get knocked down....... California had a lot of those years ago but they phased them out in favor of far-left corner heads.

I don't think California did a very good job placing its signals. Many jurisdictions around the world, including several here in North America, utilize median mounted signals without issue. What California and Nevada never did very well was placing them back from the intersection. If they are placed too close, they will get struck by wide vehicles turning left. British Columbia generally places protected left turns at least a couple of meters back from the crosswalk line.

Nevada was never really big on median signals (or at least, not to my knowledge). But you're right in that some of the ones I can think of were on narrow medians and right near the nose of the median... Current practice for nearly all jurisdictions is to just put left turn signals overhead.

There are three locations in Nevada I can think of with post-mounted signals in the median, two in Las Vegas and one in Sparks. In all cases, the posts are located on medians that are at least a traffic lane wide–although one Vegas location still puts the posts pretty close to the median nose.

It's perfectly logical why post mounted signals would be placed so close to the stop line. The agency's want to make sure that these signals are visible for traffic at the front of the line, however, traffic at the front of the line can usually see the signals in front of them or on the far left. Nearside signals are typically most helpful for cars that are more than three back.

I may have unfairly singled out Nevada and California. Judging by the photos above from Wisconsin, they also placed their median signals quite close to the median nose. So apparently, they don't have quite as many issues as we all may be thinking. Although I seem to recall new signals in Wisconsin not using median signals as often as before, so maybe there have been some issues.

Looking at other countries, such as the UK, Australia, NZ, and South Africa, median signals are all very common. Certainly the norm. Agencies in the US that want to utilize median signals just have to look at these countries for some guidance. Certainly they wouldn't use them as often if they were constantly being knocked over. The key is just to not put them so close to the edges of the medians.

jakeroot

A couple examples of all yellow signal backplates in Silverdale and Redmond, WA (respectively). The first one is definitely not allowed, but I think the second one is OK with them being bike signals...





I think these are OK, but the yellow borders seem really thick...


SignBridge

The MUTCD requires the front of backplates to be dull black. Though I know yellow backplates are common in Canada.



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