Traffic signal

[roadman65]

https://goo.gl/maps/i9seQSqjXViAeHgE6
Here is a left turn signal using both a green ball and green arrow

On the right side in the link above you can see an old mast arm still in use

Yeah. Morristown was one of the last municipalities in New Jersey to use them.  They also used the two section crosswalk heads as in the seventies they were everywhere in that town.

[jakeroot]

That mast arm reminds me of a similar mast arm in Spokane, I think it's the oldest signal in the city (W Broadway & N Lincoln):

https://goo.gl/maps/qmLzadsDa1xBNaQ68

I think they are called double-guy or something? I always thought they were neat.

[NoGoodNamesAvailable]

I love the guy wire style mast arms and it seems like NYC is the only place left that uses them at all. I wonder if they meet modern structural codes and if not how NYC gets away with it? They're much "lighter"  looking than most american mast arms.

[roadman65]

I love the guy wire style mast arms and it seems like NYC is the only place left that uses them at all. I wonder if they meet modern structural codes and if not how NYC gets away with it? They're much "lighter"  looking than most american mast arms.

NYC still uses analog controllers and none of their intersections have loops because of them. All signals are timed and change orientation whether traffic is there or not. Heck no call buttons for crosswalks either. Every minute or two the walk icon comes even if no one is walking by.

[Dirt Roads]

That mast arm reminds me of a similar mast arm in Spokane, I think it's the oldest signal in the city (W Broadway & N Lincoln):

https://goo.gl/maps/qmLzadsDa1xBNaQ68

I think they are called double-guy or something? I always thought they were neat.

Wow, there are a bunch of "double guys" associated with that particular intersection.  Indeed, the mast arms are attached with "double guys", but there are also two sets of signal wires crossing North Lincoln Street and we call those "double guys" as well.  The term "guy wire" is a nautical term adopted by railroads and their telegraph partners during the advent of telegraphy and electrified signalling.  The term refers to the use of cables to support "riggings".  So technically, the aerial support of a cable span is not a "rigging" and the only reason we call them "guy wires" is that we originally used the same type of cable as the "down guys" (guy wires used to either back-brace the pole to the ground, or in your case, guy wires used as true riggings to support a side mast).

There are actually six sets of "double guys" at this location: four "double guy" signal mast arms, another for signal wires crossing North Lincoln Street shown here, and another on the right crossing West Broadway.  But one of those "guy wires" isn't supporting anything.  If you look carefully, it is the newer of the two guy wires crossing the street (you can tell because it is self-supporting cable where the jacketed cable is twisted along with the guy wire).  (If I want to get technical here, the set crossing North Lincoln Street is actually a "triple guy" with a little flimsy self-supporting cable hanging just a few inches under the top one and not supported by the top one).

[roadman65]

https://goo.gl/maps/NuYXNz9cK5C8oUYa7
Why bother with backplates if the signal head is mounted to the beam of the bridge. The bridge blocks out the light that the back plates are designed to block out in the first place.

[roadfro]

https://goo.gl/maps/NuYXNz9cK5C8oUYa7
Why bother with backplates if the signal head is mounted to the beam of the bridge. The bridge blocks out the light that the back plates are designed to block out in the first place.

Target value for the signal head. The backplate provides greater contrast against the side of the bridge, making it easier to recognize that a signal is there at a distance, perhaps more important in case of power outage at night.

I feel more agencies are beginning to employ backplates as a standard practice in part for this reason (it's been standard in Nevada as long as I can remember). Some agencies are also embracing the optional yellow reflective border around the backplate as a defacto standard...in the Reno area, all signals within NDOT ROW have had the borders applied to existing backplates, and the cities/RTC are using them on all new signal installs/retrofits as of a couple years ago--it does help signals stand out.

[jakeroot]

That mast arm reminds me of a similar mast arm in Spokane, I think it's the oldest signal in the city (W Broadway & N Lincoln):

https://goo.gl/maps/qmLzadsDa1xBNaQ68

I think they are called double-guy or something? I always thought they were neat.

Wow, there are a bunch of "double guys" associated with that particular intersection.  Indeed, the mast arms are attached with "double guys", but there are also two sets of signal wires crossing North Lincoln Street and we call those "double guys" as well.  The term "guy wire" is a nautical term adopted by railroads and their telegraph partners during the advent of telegraphy and electrified signalling.  The term refers to the use of cables to support "riggings".  So technically, the aerial support of a cable span is not a "rigging" and the only reason we call them "guy wires" is that we originally used the same type of cable as the "down guys" (guy wires used to either back-brace the pole to the ground, or in your case, guy wires used as true riggings to support a side mast).

There are actually six sets of "double guys" at this location: four "double guy" signal mast arms, another for signal wires crossing North Lincoln Street shown here, and another on the right crossing West Broadway.  But one of those "guy wires" isn't supporting anything.  If you look carefully, it is the newer of the two guy wires crossing the street (you can tell because it is self-supporting cable where the jacketed cable is twisted along with the guy wire).  (If I want to get technical here, the set crossing North Lincoln Street is actually a "triple guy" with a little flimsy self-supporting cable hanging just a few inches under the top one and not supported by the top one).

Thank you for the detail! I was interested to know where that term came from (I guess if I was really interested, I would have consulted Google, but still -- thank you).

I notice that the mast lighting on the northwest and southwest corner also use guy-wire supporting, is this what you are referring to?

As an aside, I really like how the mast arm is at a fully right angle to the mast; almost all traffic signal mast arms these days are at a very slight angle. I don't know if this is afforded to it being a double-guy mast arm design, which are no doubt long out of production, but I still like it.

[Dirt Roads]

I notice that the mast lighting on the northwest and southwest corner also use guy-wire supporting, is this what you are referring to?

Nice.  Didn't even notice those.  No, I'm referring to the guy wire used to support the signal cables between the various masts.  That cable is strictly there to support the weight of the cable beneath.  We railroaders use the term "messenger cable" (and I believe that term has spread amongst some within the telephone cable industry and cable television industry).  It is my impression that the "messenger cable" was originally called a "guy wire" because part of the purpose is truly related to "rigging", that is keeping the distance between the masts (or poles) at a relatively fixed maximum length that will prevent the supported cable beneath from snapping.  You've probably seen places in "curves" on power lines where a pole is mounted on the opposite side of the road for no apparent reason.  The two poles are connected with a true guy wire that prevents the powerline pole from bending into the curve.  That second pole also gets a one or more "down guys" as structural support to deal with the additional forces placed on both poles due to wind (on the powerlines themselves).

As an aside, I really like how the mast arm is at a fully right angle to the mast; almost all traffic signal mast arms these days are at a very slight angle. I don't know if this is afforded to it being a double-guy mast arm design, which are no doubt long out of production, but I still like it.

That's a great physics problem.  It takes a much stronger cantilever structure to support a perpendicular mast than it does when the mast is bent at a slight angle.  But these guys solved that problem with "down guys".  Nifty and thrifty.

[jakeroot]

I notice that the mast lighting on the northwest and southwest corner also use guy-wire supporting, is this what you are referring to?

Nice.  Didn't even notice those.  No, I'm referring to the guy wire used to support the signal cables between the various masts.  That cable is strictly there to support the weight of the cable beneath.  We railroaders use the term "messenger cable" (and I believe that term has spread amongst some within the telephone cable industry and cable television industry).  It is my impression that the "messenger cable" was originally called a "guy wire" because part of the purpose is truly related to "rigging", that is keeping the distance between the masts (or poles) at a relatively fixed maximum length that will prevent the supported cable beneath from snapping.  You've probably seen places in "curves" on power lines where a pole is mounted on the opposite side of the road for no apparent reason.  The two poles are connected with a true guy wire that prevents the powerline pole from bending into the curve.  That second pole also gets a one or more "down guys" as structural support to deal with the additional forces placed on both poles due to wind (on the powerlines themselves).

Thank you for the extra information, I was having some issues parsing what you were describing. But then of course I was, because I've never heard of a messenger cable, that is awesome. Just looking at it, I thought those were two separate cables.

As an aside, I really like how the mast arm is at a fully right angle to the mast; almost all traffic signal mast arms these days are at a very slight angle. I don't know if this is afforded to it being a double-guy mast arm design, which are no doubt long out of production, but I still like it.

That's a great physics problem.  It takes a much stronger cantilever structure to support a perpendicular mast than it does when the mast is bent at a slight angle.  But these guys solved that problem with "down guys".  Nifty and thrifty.

I suppose it helps that they only had to hang one signal, since the supplemental signals are on the left and right poles. Though I'm sure down guys would have been strong enough with a right-angle signal to support more than one.

[roadman65]

https://goo.gl/maps/Kfb1yUuCFJfnXDHJ7
The pedestrian signal head in Vandalia, IL uses the standard housing of a normal 12 inch signal section here.  That is very strange.

https://goo.gl/maps/kgJg17CQGok9Yy6F8
Here's the front side.

[jakeroot]

https://goo.gl/maps/Kfb1yUuCFJfnXDHJ7
The pedestrian signal head in Vandalia, IL uses the standard housing of a normal 12 inch signal section here.  That is very strange.

https://goo.gl/maps/kgJg17CQGok9Yy6F8
Here's the front side.

As far as I know, not strange at all. Where I come from (WA), it's very rare. But some places use them a lot. Washington DC is a well known user of this exact type of pedestrian signal housing.

[roadman65]

Well I found one that is only unique to NJ.  I posted it in another thread but one of the resident trolls here, was the only response. He said my GSV image of last Summer was years old, and from past experiences has no clue how New Jersey operates signals despite being a road enthusiast and living in New Jersey which my image pointed out.

Anyway looks like no other user found a state besides New Jersey that fails to use green arrows on split phases, so that is a Jersey thing. 

[fwydriver405]

Well I found one that is only unique to NJ.  I posted it in another thread but one of the resident trolls here, was the only response. He said my GSV image of last Summer was years old, and from past experiences has no clue how New Jersey operates signals despite being a road enthusiast and living in New Jersey which my image pointed out.

Anyway looks like no other user found a state besides New Jersey that fails to use green arrows on split phases, so that is a Jersey thing. 

It sometimes happens at some older installs at some Maine (1*,2,3) and New Hampshire (1^,2) intersections, though this is starting to be less of an issue when signals are being replaced (NH: Old, New) or retrofitted (Maine: Old, New). In the cases of Maine and NH, the approaches may have initally be permissive only when it was installed and then some situation required the intersection to be changed to split.

*This is a fully split-phased intersection. Only the Bangor Mall Rd approach has this issue - the left turn signal has circular RYG indications.
^This intersection is getting new signals and phasing in the near future - it has been phased and set up this way since the mid 80s or 90s from when this signal was first installed.

[Caps81943]

Also happens at this intersection in Virginia:

https://www.google.com/maps/@39.1681231,-78.0047146,3a,75y,351.58h,88.04t/data=!3m6!1e1!3m4!1scfjVyTiOW5xoFeo8w89s4g!2e0!7i13312!8i6656?entry=ttu

Oddly enough, the light at the other end of town is basically an identical intersection, but has typical split phasing signalization.

[Hobart]

So I'm back in Chicagoland for the weekend, and my family was driving home from an Italian restaurant in Tinley Park, when I noticed these doohickeys mounted over the red signal lenses on 183rd and Harlem:


Does anybody know what these are for or why they put them on? My two suspicions are to either somehow focus the red light towards the direction the signal controls, or to prevent ice and snow buildup.

[fwydriver405]

So I'm back in Chicagoland for the weekend, and my family was driving home from an Italian restaurant in Tinley Park, when I noticed these doohickeys mounted over the red signal lenses on 183rd and Harlem:

(Image snipped)

Does anybody know what these are for or why they put them on? My two suspicions are to either somehow focus the red light towards the direction the signal controls, or to prevent ice and snow buildup.

I think they are for preventing ice and snow buildup on the signals (Sources: 1, 2)

[fwydriver405]

I got to see Montréal's way of displaying an LPI (or LTI, Leading Thru Interval) when I went to Montréal two weeks ago in person and it reminded me of another signal sequence that is very similar around the Los Angeles area for LTIs.

This is for a permissive and/or permissive/protected setup. For the LTI:
- In Montreal, the signal starts with a upward-facing green arrow when "WALK" is displayed. It changes to a circular green after the LTI ends. There is a 5 and 6-section version of this signal, with the indications being (R-Y-G-UfGA-LtYA-LtFGA). LtYA is omitted in the 5 section version and it also could have a transit bypass signal as well on the top instead of LFGA. The ones with left turn phasing were all lagging left.

- In Los Angeles (circular red-red arrow signal), the signal starts with both a red arrow AND circular green when "WALK" is displayed. It changes to a circular green after the LTI ends. (The LA setup shown here was changed to a fully protected setup with seperate signals)

Obviously, having separate signals (and dedicated turn lanes) for each movement with FYA works a lot better for signalling this operation. Besides this, I'm curious to see which one is better for signalling this operation: Montréal or Los Angeles?

[PurdueBill]

I got to see Montréal's way of displaying an LPI (or LTI, Leading Thru Interval) when I went to Montréal two weeks ago in person and it reminded me of another signal sequence that is very similar around the Los Angeles area for LTIs.

This is for a permissive and/or permissive/protected setup. For the LTI:
- In Montreal, the signal starts with a upward-facing green arrow when "WALK" is displayed. It changes to a circular green after the LTI ends. There is a 5 and 6-section version of this signal, with the indications being (R-Y-G-UfGA-LtYA-LtFGA). LtYA is omitted in the 5 section version and it also could have a transit bypass signal as well on the top instead of LFGA. The ones with left turn phasing were all lagging left.

- In Los Angeles (circular red-red arrow signal), the signal starts with both a red arrow AND circular green when "WALK" is displayed. It changes to a circular green after the LTI ends. (The LA setup shown here was changed to a fully protected setup with seperate signals)

Obviously, having separate signals (and dedicated turn lanes) for each movement with FYA works a lot better for signalling this operation. Besides this, I'm curious to see which one is better for signalling this operation: Montréal or Los Angeles?

The LA one has something the Montreal one lacks--an explicit indication against left turns while straight is allowed. Something about the straight green arrow but nothing at all about lefts makes me worry that people might think either the signal is "broken" and lefts are allowed but dark, or that there is no signal phase at all relating to left turns (go whenever).  The red arrow seems good to say "we didn't forget left turns--don't do it right now."

[jakeroot]

- In Los Angeles (circular red-red arrow signal), the signal starts with both a red arrow AND circular green when "WALK" is displayed. It changes to a circular green after the LTI ends. (The LA setup shown here was changed to a fully protected setup with seperate signals)

That setup is identical to this current LPI in Spokane, WA. Red arrow at the beginning during the LPI, before being extinguished and only a green orb is displayed.

Unfortunately, I cannot find a GSV showing a green orb + red arrow. And, investigating GSV for a bit, there is some evidence that the LPI may not always be active: these cars are setting off at a freshly green light, but there is only green orbs, and the "Don't Walk" sign is displayed.

[mrsman]

I got to see Montréal's way of displaying an LPI (or LTI, Leading Thru Interval) when I went to Montréal two weeks ago in person and it reminded me of another signal sequence that is very similar around the Los Angeles area for LTIs.

This is for a permissive and/or permissive/protected setup. For the LTI:
- In Montreal, the signal starts with a upward-facing green arrow when "WALK" is displayed. It changes to a circular green after the LTI ends. There is a 5 and 6-section version of this signal, with the indications being (R-Y-G-UfGA-LtYA-LtFGA). LtYA is omitted in the 5 section version and it also could have a transit bypass signal as well on the top instead of LFGA. The ones with left turn phasing were all lagging left.

- In Los Angeles (circular red-red arrow signal), the signal starts with both a red arrow AND circular green when "WALK" is displayed. It changes to a circular green after the LTI ends. (The LA setup shown here was changed to a fully protected setup with seperate signals)

Obviously, having separate signals (and dedicated turn lanes) for each movement with FYA works a lot better for signalling this operation. Besides this, I'm curious to see which one is better for signalling this operation: Montréal or Los Angeles?

The LA one has something the Montreal one lacks--an explicit indication against left turns while straight is allowed. Something about the straight green arrow but nothing at all about lefts makes me worry that people might think either the signal is "broken" and lefts are allowed but dark, or that there is no signal phase at all relating to left turns (go whenever).  The red arrow seems good to say "we didn't forget left turns--don't do it right now."

I agree.  From a US perspective, we prefer to see a NO indication as opposed to understanding that a straight arrow implies no turns.  In the US, the Montreal signal is a no-go.  I don't know how the Montreal signal is interpreted in Canada.  It seems that Quebec allows for right on red, except on the island of Montreal.

And it seems like its common there.

Take a look at this sign.

https://www.google.com/maps/@45.5785795,-73.5600436,3a,75y,224.68h,98.99t/data=!3m6!1e1!3m4!1sJboCjJvi8r4o3peU5iRFCg!2e0!7i16384!8i8192?hl=en&entry=ttu

It is striaght and right in a green circle.  Can you turn left here?  Since only straight and right are in the green circle, left turns are prohibited.  In the US, the would have a no left turn sign instead.

- In Los Angeles (circular red-red arrow signal), the signal starts with both a red arrow AND circular green when "WALK" is displayed. It changes to a circular green after the LTI ends. (The LA setup shown here was changed to a fully protected setup with seperate signals)

That setup is identical to this current LPI in Spokane, WA. Red arrow at the beginning during the LPI, before being extinguished and only a green orb is displayed.

Unfortunately, I cannot find a GSV showing a green orb + red arrow. And, investigating GSV for a bit, there is some evidence that the LPI may not always be active: these cars are setting off at a freshly green light, but there is only green orbs, and the "Don't Walk" sign is displayed.

And that is a good thing.  As there are pedestrian activation buttons, the LPI should only be operational when the WALK signal is operational.  If no pedestrian pushes the button, there is no need for an LPI.

[RobbieL2415]

I got to see Montréal's way of displaying an LPI (or LTI, Leading Thru Interval) when I went to Montréal two weeks ago in person and it reminded me of another signal sequence that is very similar around the Los Angeles area for LTIs.

This is for a permissive and/or permissive/protected setup. For the LTI:
- In Montreal, the signal starts with a upward-facing green arrow when "WALK" is displayed. It changes to a circular green after the LTI ends. There is a 5 and 6-section version of this signal, with the indications being (R-Y-G-UfGA-LtYA-LtFGA). LtYA is omitted in the 5 section version and it also could have a transit bypass signal as well on the top instead of LFGA. The ones with left turn phasing were all lagging left.

- In Los Angeles (circular red-red arrow signal), the signal starts with both a red arrow AND circular green when "WALK" is displayed. It changes to a circular green after the LTI ends. (The LA setup shown here was changed to a fully protected setup with seperate signals)

Obviously, having separate signals (and dedicated turn lanes) for each movement with FYA works a lot better for signalling this operation. Besides this, I'm curious to see which one is better for signalling this operation: Montréal or Los Angeles?

There's also this LPI near where I live, which has protected turn movements and a variable sign that lights up "No Turn on Red" or "Turning Vehicles YIELD to pedestrians" when the crosswalk signal is activated.
https://www.google.com/maps/@41.8061236,-72.5548704,3a,75y,28.4h,87.7t/data=!3m7!1e1!3m5!1sVkdqPgietaeuEezH6uz7mQ!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DVkdqPgietaeuEezH6uz7mQ%26cb_client%3Dmaps_sv.tactile.gps%26w%3D203%26h%3D100%26yaw%3D336.40787%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192?hl=en&entry=ttu

[chrisg69911]

Well I found one that is only unique to NJ.  I posted it in another thread but one of the resident trolls here, was the only response. He said my GSV image of last Summer was years old, and from past experiences has no clue how New Jersey operates signals despite being a road enthusiast and living in New Jersey which my image pointed out.

Anyway looks like no other user found a state besides New Jersey that fails to use green arrows on split phases, so that is a Jersey thing.

Here is an example. Only one direction goes at a time. It runs in a counterclockwise circle.
https://www.google.com/maps/@40.8443755,-74.0784353,3a,44.9y,289.08h,93.51t/data=!3m7!1e1!3m5!1smIPQyuVgOUKjWRBQSUEcbw!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fpanoid%3DmIPQyuVgOUKjWRBQSUEcbw%26cb_client%3Dmaps_sv.tactile.gps%26w%3D203%26h%3D100%26yaw%3D286.45612%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192?entry=ttu

[roadman65]

https://goo.gl/maps/4ezbNYtWaALzTbqg6
This is unusual. Normally New Jersey signals are not mounted this way at the end of the truss arm.  They hang from a chain and sway and not at all mounted to non moving brackets.

Anyone who lives in NJ can contest to this.

[jakeroot]

https://goo.gl/maps/4ezbNYtWaALzTbqg6
This is unusual. Normally New Jersey signals are not mounted this way at the end of the truss arm.  They hang from a chain and sway and not at all mounted to non moving brackets.

Anyone who lives in NJ can contest to this.

I'm sure this is now the norm for new installations? Not really sure as I don't live out that way, but I don't recall hanging signals on new installations that I've seen linked here and from browsing around NJ on Google Maps.