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Traffic signal

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

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mrsman

Quote from: roadfro on May 28, 2024, 11:17:17 AM
Quote from: ErmineNotyours on May 27, 2024, 11:36:08 PMT-intersection, the left lane turns left only, the right lane turns right only.  Yet there are two left turn light assemblies and only one for the right lane and turn.  I thought the right turn was supposed to get the redundancy.  https://maps.app.goo.gl/wemEMqtz6B6n3tcKA
I assume the left turn is the prevailing movement here. MUTCD says if there is not a through movement on an approach, then the dominant movement must have two primary signal faces.

In my view, though, every signalized movement should have at least two signal faces for redundancy.

I agree that there should be more redundancy for each shown movement.  I'm not sure of what the MUTCD now requires, but a lot of this can be done with fewer signal faces, but more light bulbs.  One possibility is to show two doghouses (Red orb, Y left arrow, Y right arrow, G left arrow, G right arrow).  Red orb is lit, unless both of the other arrows are either yellow or green.  Another possibility is three signal faces, with left and right as existing and the middle signal face being the doghouse I describe above.


SignBridge

#5276
The MUTCD requires a minimum of two signal heads for the through movement, but not for other movements even when a turning movement might actually be the predominant movement. The number of heads for turning movements is left up to engineering judgment.


jeffandnicole

There's this signal on Salem CR 605 (Swedesboro Road) to a connector road (High Bridge Bypass Road) to NJ 45: https://maps.app.goo.gl/UsGBRtZUdDj4SfU8A  Click forwards or backwards to see the different sets of arrows flash.

The 2 signals in front flash left yellow arrows; the 3 signals in the back flash red left arrows.  The purpose is to encourage traffic to turn left without proceeding straight into a dead end.

The last few times I've been down here, only the yellow arrows were flashing.  Either the red arrows were turned off, or not working.


Revive 755

^ see.
Quote from: SignBridge on May 28, 2024, 09:44:23 PMThe MUTCD requires a minimum of two signal heads for the through movement, but not for other movements even when a turning movement might actually be the predominant movement. The number of heads for turning movements is left up to engineering judgment.

That is unless the new 2023 Manual says something different. Anybody know for sure?

Doesn't look like the new version has changed much from the 2009 version in regards to the number of heads for turns with no through lanes.

Quote from: MUTCD 11th Edition Paragraph 01A. If a signalized motor vehicle through movement exists on an approach, a minimum of two primary
signal faces shall be provided for the through movement. Except for single lane approaches, if a signalized motor vehicle through movement does not exist on an approach, a minimum of two primary signal faces shall be provided for the signalized motor vehicle turning movement that is considered to be the major movement from the approach (also see Section 4F.16).

Quote from: 11th MUTCD Edition 4F.16 Paragraph 02Except for single-lane approaches, a minimum of two primary signal faces shall be provided for the signalized turning movement that is considered to be the major movement from the approach (see Section 4D.05).
- -
Quote from: mrsman on May 28, 2024, 09:29:27 PMI agree that there should be more redundancy for each shown movement.  I'm not sure of what the MUTCD now requires, but a lot of this can be done with fewer signal faces, but more light bulbs.  One possibility is to show two doghouses (Red orb, Y left arrow, Y right arrow, G left arrow, G right arrow).  Red orb is lit, unless both of the other arrows are either yellow or green.  Another possibility is three signal faces, with left and right as existing and the middle signal face being the doghouse I describe above.

If you change the middle head to a doghouse there's a greater risk someone will get confused and treat the left lane as also allowing right turns, especially if the arrows on the pavement fade or are otherwise hard to see.

mrsman

Quote from: jeffandnicole on May 28, 2024, 09:47:37 PMThere's this signal on Salem CR 605 (Swedesboro Road) to a connector road (High Bridge Bypass Road) to NJ 45: https://maps.app.goo.gl/UsGBRtZUdDj4SfU8A  Click forwards or backwards to see the different sets of arrows flash.

The 2 signals in front flash left yellow arrows; the 3 signals in the back flash red left arrows.  The purpose is to encourage traffic to turn left without proceeding straight into a dead end.

The last few times I've been down here, only the yellow arrows were flashing.  Either the red arrows were turned off, or not working.



I would think that red arrows are a problem as they would imply a stopping condition.

CJResotko


freebrickproductions

Quote from: CJResotko on May 27, 2024, 05:48:38 PMApparently, there are a lot of abandoned worded pedestrian signals within the town of Bellaire, Ohio.
The intersections they're at used to be controlled by traffic signals, but they all got removed sometime between 2009 and 2015, and they left the pedestrian signals behind (along with overhead signs at some intersections). I found 9 intersections that are like this!
Here's just one of them: https://www.google.com/maps/@40.0119205,-80.7441845,3a,15y,82.84h,93.54t/data=!3m6!1e1!3m4!1sfbZcXniGb53uaVDOOc5ypw!2e0!7i16384!8i8192?entry=ttu

Seen a few like that here in Alabama. Also seen them abandoned at intersections where the traffic lights are still in use!

Quote from: thenetwork on May 27, 2024, 08:39:45 PMI wonder if you can contact the city and ask if you could "dis-assemble" one for a small donation to the city?

I've honestly thought about doing that for this for a couple of abandoned signals in my area, such as this fiber-optic Winkomatic signal in Attalla, AL, or one of these Krossgard signals in Albertville, AL.

Quote from: thenetwork on May 27, 2024, 08:39:45 PMPersonally, those are a little too modern for my tastes.  I would jump at the chance if they were older metal crossing fixtures.

TBF, they are aluminum, but they are 12 inch LFE peds. Not that I wouldn't mind one myself, of course. :)
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)


SilverMustang2011

This signal in the depths of urban Jacksonville was removed sometime between 2011 and 2013 but this may have been the oldest operating signal in Florida, and one of the few single-light intersections in the state, before that: https://maps.app.goo.gl/Z4BP8Vw22xYS5vFGA

It also appears to have been converted to at least partial LED before being removed.

freebrickproductions

A Crouse-hinds Art-deco 4-way! Not aware of many others down there, definitely a shame it's gone now.

And it appears that was fully LED prior to removal. A shame they didn't just double it up with a few extra heads.
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)

SilverMustang2011

Quote from: freebrickproductions on June 07, 2024, 09:35:45 PMA Crouse-hinds Art-deco 4-way! Not aware of many others down there, definitely a shame it's gone now.

And it appears that was fully LED prior to removal. A shame they didn't just double it up with a few extra heads.

You'd know more about how old that signal was than me, but it's crazy that it survived with all the changes around it (I-95 and I-10, the neighborhood decay, etc.)

It's unfortunate that the light wasn't in the gentrified part of Brooklyn, because if it was better known someone may have wanted to preserve it (Even if it was just a display) when they started rebuilding that area. Then again, Jacksonville is only just now actively trying to build a history center, so maybe not.

roadman65

https://www.flickr.com/photos/54480415@N08/53778107675
I was noticing that in Kansas their MUTCD requires a side mount signal on all signal installations that's mounted to the pole supporting the mast arm.

Does anyone know the rationale behind this?
Every day is a winding road, you just got to get used to it.

Sheryl Crowe

Big John

Quote from: roadman65 on June 10, 2024, 09:45:41 AMhttps://www.flickr.com/photos/54480415@N08/53778107675
I was noticing that in Kansas their MUTCD requires a side mount signal on all signal installations that's mounted to the pole supporting the mast arm.

Does anyone know the rationale behind this?
There may be a couple semis blocking the view if the signals on the mast arm so this may be the only visible signal.

roadman65

Quote from: Big John on June 10, 2024, 09:58:17 AM
Quote from: roadman65 on June 10, 2024, 09:45:41 AMhttps://www.flickr.com/photos/54480415@N08/53778107675
I was noticing that in Kansas their MUTCD requires a side mount signal on all signal installations that's mounted to the pole supporting the mast arm.

Does anyone know the rationale behind this?
There may be a couple semis blocking the view if the signals on the mast arm so this may be the only visible signal.

Be great if all states do this.^^^^^




https://www.flickr.com/photos/54480415@N08/52133892553
I was going through my AL photos and noticed that Alabama uses flashers on on a two section signal head rather than two separate  one sections.

Is this still allowed by the MUTCD.

New Jersey uses these but with both flashing together. AL uses alternate flashing.
Every day is a winding road, you just got to get used to it.

Sheryl Crowe

freebrickproductions

Double beacons are by and large the standard here, you can find some traditional one-section beacons though.

I believe they'll put up extra faces for roads that have two or more lanes on approach, but not always.
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)

roadman65

Quote from: freebrickproductions on June 10, 2024, 02:07:42 PMDouble beacons are by and large the standard here, you can find some traditional one-section beacons though.

I believe they'll put up extra faces for roads that have two or more lanes on approach, but not always.


I've seen that on US 231 at US 278. It's a four way stop ( or was in 2005) and both lanes of US 231 had separate flasher heads. When one was up, the other was down to give a zig zag effect to drivers.
Every day is a winding road, you just got to get used to it.

Sheryl Crowe

freebrickproductions

Quote from: roadman65 on June 10, 2024, 03:06:37 PM
Quote from: freebrickproductions on June 10, 2024, 02:07:42 PMDouble beacons are by and large the standard here, you can find some traditional one-section beacons though.

I believe they'll put up extra faces for roads that have two or more lanes on approach, but not always.


I've seen that on US 231 at US 278. It's a four way stop ( or was in 2005) and both lanes of US 231 had separate flasher heads. When one was up, the other was down to give a zig zag effect to drivers.

They've replaced the signals there since, sadly. US 231 now only has one head per approach, though US 278 still retains two per approach. The next 4-way stop to the east of there however, US 278/AL 79, does retain one of those "quad-beacons" at it though.

Slightly unrelated, but Irondale also has this interesting beacon set-up. It normally flashes yellow, but when a car approaches, it starts flashing red. When I was there, the vehicular detection for it didn't entirely seem to be the best, especially if a car approached just as it was returning to the yellow flash.
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)

wanderer2575

Quote from: freebrickproductions on June 10, 2024, 05:05:26 PMSlightly unrelated, but Irondale also has this interesting beacon set-up. It normally flashes yellow, but when a car approaches, it starts flashing red. When I was there, the vehicular detection for it didn't entirely seem to be the best, especially if a car approached just as it was returning to the yellow flash.

WTF??!  What's the point of a yellow flash phase if it will always change to red when a vehicle approaches?  And there isn't a programmed minimum delay between phases; gotta love how it changes to flashing yellow for a millisecond before going back to flashing red.  Has this thing induced any seizures?

thenetwork

Quote from: Big John on June 10, 2024, 09:58:17 AM
Quote from: roadman65 on June 10, 2024, 09:45:41 AMhttps://www.flickr.com/photos/54480415@N08/53778107675
I was noticing that in Kansas their MUTCD requires a side mount signal on all signal installations that's mounted to the pole supporting the mast arm.

Does anyone know the rationale behind this?
There may be a couple semis blocking the view if the signals on the mast arm so this may be the only visible signal.

Not to mention if you are driving into direct sunlight, you may not see the overhead signals either due to the glare or your sun visor. 

With a side-mounted signal at a lower angle, it gives a driver another safer option to view the light.

mrsman

Quote from: thenetwork on June 10, 2024, 06:42:43 PM
Quote from: Big John on June 10, 2024, 09:58:17 AM
Quote from: roadman65 on June 10, 2024, 09:45:41 AMhttps://www.flickr.com/photos/54480415@N08/53778107675
I was noticing that in Kansas their MUTCD requires a side mount signal on all signal installations that's mounted to the pole supporting the mast arm.

Does anyone know the rationale behind this?
There may be a couple semis blocking the view if the signals on the mast arm so this may be the only visible signal.

Not to mention if you are driving into direct sunlight, you may not see the overhead signals either due to the glare or your sun visor. 

With a side-mounted signal at a lower angle, it gives a driver another safer option to view the light.

Many western states seem to have side mounted signals as a standard.  For the reasons you mentioned, I wished that it was a practice adopted everywhere. 

roadman65

#5295
Quote from: mrsman on June 11, 2024, 10:19:27 AM
Quote from: thenetwork on June 10, 2024, 06:42:43 PM
Quote from: Big John on June 10, 2024, 09:58:17 AM
Quote from: roadman65 on June 10, 2024, 09:45:41 AMhttps://www.flickr.com/photos/54480415@N08/53778107675
I was noticing that in Kansas their MUTCD requires a side mount signal on all signal installations that's mounted to the pole supporting the mast arm.


Does anyone know the rationale behind this?
There may be a couple semis blocking the view if the signals on the mast arm so this may be the only visible signal.

Not to mention if you are driving into direct sunlight, you may not see the overhead signals either due to the glare or your sun visor. 

With a side-mounted signal at a lower angle, it gives a driver another safer option to view the light.

Many western states seem to have side mounted signals as a standard.  For the reasons you mentioned, I wished that it was a practice adopted everywhere. 

California and Arizona I know use both a near and far sided side mounts on the right.

New Jersey ( and now Bucks County, PA) use a left side overhead on the opposing side mast arm providing a left turn signal isn't used.  That allows to see around the left of a semi in front of you.

The Garden State used to on divided highways post a median side mount and additional mast arm extending from the median to add additional signaling to give plenty vantage points.

Here's one still used in latest GSV imagery on US 9 in Monmouth County, NJ.
https://maps.app.goo.gl/9SwRtPcJ4cqE6kS48
https://maps.app.goo.gl/2KdQmG9te8WPsCxh7
Every day is a winding road, you just got to get used to it.

Sheryl Crowe

steviep24

#5296
Span wire traffic signals at JFK Airport. I found more but no need to post them.

https://www.google.com/maps/@40.659083,-73.7743048,3a,75y,233.78h,90t/data=!3m7!1e1!3m5!1svCgDaQ-DquHxTZNKetQrfg!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DvCgDaQ-DquHxTZNKetQrfg%26cb_client%3Dmaps_sv.share%26w%3D900%26h%3D600%26yaw%3D233.78072557271972%26pitch%3D0%26thumbfov%3D90!7i16384!8i8192?authuser=0&coh=205410&entry=ttu

https://www.google.com/maps/@40.659642,-73.7760605,3a,75y,298.4h,90t/data=!3m7!1e1!3m5!1sgfO0CevE2q3wK1MvrD4n4A!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DgfO0CevE2q3wK1MvrD4n4A%26cb_client%3Dmaps_sv.share%26w%3D900%26h%3D600%26yaw%3D298.40072557272026%26pitch%3D0%26thumbfov%3D90!7i16384!8i8192?authuser=0&coh=205410&entry=ttu

https://www.google.com/maps/@40.6606178,-73.7791055,3a,75y,298.4h,90t/data=!3m7!1e1!3m5!1sbcnMkzzYIgZiPGbiSAgBJw!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DbcnMkzzYIgZiPGbiSAgBJw%26cb_client%3Dmaps_sv.share%26w%3D900%26h%3D600%26yaw%3D298.40072557272026%26pitch%3D0%26thumbfov%3D90!7i16384!8i8192?authuser=0&coh=205410&entry=ttu

https://www.google.com/maps/@40.6631637,-73.7874493,3a,75y,283.89h,90t/data=!3m7!1e1!3m5!1syC3M43w90mlEFIyB2eIuRQ!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DyC3M43w90mlEFIyB2eIuRQ%26cb_client%3Dmaps_sv.share%26w%3D900%26h%3D600%26yaw%3D283.89425631831995%26pitch%3D0%26thumbfov%3D90!7i16384!8i8192?authuser=0&coh=205410&entry=ttu

roadman65

https://maps.app.goo.gl/icPTWbnjs75b9bq26
Round backplates on Market Street in San Fran.
Every day is a winding road, you just got to get used to it.

Sheryl Crowe

SignBridge

Quote from: roadman65 on June 18, 2024, 08:46:32 PMhttps://maps.app.goo.gl/icPTWbnjs75b9bq26
Round backplates on Market Street in San Fran.

Those have been there many years, probably since the 1980's if I recall.

PColumbus73




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