Traffic signal

[Mdcastle]

What's the logic in downgrading masts to wires?

[freebrickproductions]

What's the logic in downgrading masts to wires?

Higher wind resistance.
Here in Huntsville, when the city installed new signals along Airport Road after an F4 tornado tore out all of the old ones in 1989, they installed all of the signals on span wires even though some of the old ones were on masts for the added wind resistance.
Span signals may have a tendency to get blown around in the wind, but the supporting structure is less likely to collapse in high winds, from what I understand.

[roadman65]

I was noticing that in Fort Worth, Texas the signals there are NOT horizontal like the rest of Texas.  I even noticed that it extended outside the city limits as well.  Going east they were all along the IH 30 up until Arlington.

Am I to assume that its Tarrant County that prefers standard signals in which I was seeing?  I also know that San Antonio and Galveston both use standard as well, but not in their metro areas surrounding so much.  I was just wondering what Fort Worth area signals have in common that use them.  Not that I have anything against them, but I just cannot find the defined boundary of where the vertical ends and the rest of Texas begins so I am assuming that that is Tarrant County's rule to use vertical without backplates just as SA and Galveston have done.

BTW having different assemblies throughout Texas makes signaling more interesting between the black heads in Greater Houston to some span wires in suburban and rural areas to the rest being curved mast arms or straight arms all throughout the Lone Star State.

[cl94]

What's the logic in downgrading masts to wires?

Higher wind resistance.
Here in Huntsville, when the city installed new signals along Airport Road after an F4 tornado tore out all of the old ones in 1989, they installed all of the signals on span wires even though some of the old ones were on masts for the added wind resistance.
Span signals may have a tendency to get blown around in the wind, but the supporting structure is less likely to collapse in high winds, from what I understand.

Funny, because the opposite is, from what I've been told, why NYSDOT Region 5 is mainly using mast arms from now on outside of temporary installations. Buffalo area winds are, on many days, over 20 mph steady and higher is not uncommon. They've recently had a lot of issues with signals falling during the heavy gusts this area is known for and the mast arms show little movement.

[UCFKnights]

What's the logic in downgrading masts to wires?

The only thing I can think of is that the state came up with this plan a very, very long time ago, and bid it as such. The county has upgraded various intersecting roads and put the mast arms in with accommodations for this expansion, for the state decided not to change their spec to account for that. It doesn't make much sense why they are replacing  mast arms that were put are only a few years old.

I know here in Florida, they say the mast arms are generally hurricane ready while the span wires are not. I know in South Florida when we had the last 3 hurricanes, very few mast arms failed and the signals remainend intact (minus cameras and backlit street signs). Nearly every span wire lost every signal. Their big reason for not for not doing more mast arms is that the cost is double, and even more when the arms are especially long.

[roadfro]

What's the logic in downgrading masts to wires?

Higher wind resistance.
Here in Huntsville, when the city installed new signals along Airport Road after an F4 tornado tore out all of the old ones in 1989, they installed all of the signals on span wires even though some of the old ones were on masts for the added wind resistance.
Span signals may have a tendency to get blown around in the wind, but the supporting structure is less likely to collapse in high winds, from what I understand.

A mast arm, properly designed and installed, can have high wind resistance. This is why some places with high winds (or frequent high wind potential) either tend to have mast arms or are making that conversion.

Another consideration is the cost long term. While mast arm signals probably cost twice as much in the initial installation, that is potentially offset by long-term maintenance costs. Span wire installations have to have tension wires periodically tightened and are more susceptible to damage in winds.

[AndyMax25]

Check out this traffic signal in the background go haywire.  The battery backup controller was failing.

[Bruce]

Apparently traffic lights aren't high enough for this rental truck driver:





1st & Marion in Seattle this morning.

[DaBigE]

Apparently traffic lights aren't high enough for this rental truck driver:

...[photos removed]...

1st & Marion in Seattle this morning.

Had the steep incline not been present immediately downstream of the signal, the truck probably would have had enough clearance.

[jakeroot]

Apparently traffic lights aren't high enough for this rental truck driver:

...[photos removed]...

1st & Marion in Seattle this morning.

Had the steep incline not been present immediately downstream of the signal, the truck probably would have had enough clearance.

This doesn't happen a lot, but perhaps they should take a hint and put the signals on the sides of the street, like they do at other intersections downtown.

[jeffandnicole]

Apparently traffic lights aren't high enough for this rental truck driver:

...[photos removed]...

1st & Marion in Seattle this morning.

Had the steep incline not been present immediately downstream of the signal, the truck probably would have had enough clearance.

This doesn't happen a lot, but perhaps they should take a hint and put the signals on the sides of the street, like they do at other intersections downtown.

Um, there are no signals above the street here:  https://goo.gl/maps/ZvJ1X . 

Looks like he just took the curve too sharp, and the light got hung up or imbedded in the door of that truck.

[jakeroot]

Apparently traffic lights aren't high enough for this rental truck driver:

...[photos removed]...

1st & Marion in Seattle this morning.

Had the steep incline not been present immediately downstream of the signal, the truck probably would have had enough clearance.

This doesn't happen a lot, but perhaps they should take a hint and put the signals on the sides of the street, like they do at other intersections downtown.

Um, there are no signals above the street here:  https://goo.gl/maps/ZvJ1X . 

Looks like he just took the curve too sharp, and the light got hung up or [e]mbedded in the door of that truck.

Touché. I cannot see any other hanging signals in the photo nor any wires. It would appear he snagged the southern signal facing Marion turning right from 1st Ave (N) towards Marion.

[mrsman]

Apparently traffic lights aren't high enough for this rental truck driver:

...[photos removed]...

1st & Marion in Seattle this morning.

Had the steep incline not been present immediately downstream of the signal, the truck probably would have had enough clearance.

This doesn't happen a lot, but perhaps they should take a hint and put the signals on the sides of the street, like they do at other intersections downtown.

Um, there are no signals above the street here:  https://goo.gl/maps/ZvJ1X . 

Looks like he just took the curve too sharp, and the light got hung up or [e]mbedded in the door of that truck.

Touché. I cannot see any other hanging signals in the photo nor any wires. It would appear he snagged the southern signal facing Marion turning right from 1st Ave (N) towards Marion.

The discussion begs the question as to what height signals should be hung at.  (Excuse grammar).   While I have seen low clearance signs and recently posted about the low R/R bridge above Gregson Street in Durham, NC that is frequently struck by trucks, I have never seen a low clearance sign in relation to signals hung on a wire (or a mast arm). 

[jeffandnicole]

Apparently traffic lights aren't high enough for this rental truck driver:

...[photos removed]...

1st & Marion in Seattle this morning.

Had the steep incline not been present immediately downstream of the signal, the truck probably would have had enough clearance.

This doesn't happen a lot, but perhaps they should take a hint and put the signals on the sides of the street, like they do at other intersections downtown.

Um, there are no signals above the street here:  https://goo.gl/maps/ZvJ1X . 

Looks like he just took the curve too sharp, and the light got hung up or [e]mbedded in the door of that truck.

Touché. I cannot see any other hanging signals in the photo nor any wires. It would appear he snagged the southern signal facing Marion turning right from 1st Ave (N) towards Marion.

The discussion begs the question as to what height signals should be hung at.  (Excuse grammar).   While I have seen low clearance signs and recently posted about the low R/R bridge above Gregson Street in Durham, NC that is frequently struck by trucks, I have never seen a low clearance sign in relation to signals hung on a wire (or a mast arm). 

Obviously, signals are supposed to be above the minimum height for trucks.  In most cases, they are going to be about 15' or higher at their low point above the road.  In this case, the rental truck would've only been about 11 feet high, so clearly the light wouldn't have been that low as buses are usually a little taller, and tractor trailers are 2.5 - 3 feet taller.   Traffic lights are fairly cheap, so there's no reason to have one below the minimum height requirements for all normal vehicles (trucks, buses, cars, etc).

[Big John]

^^ MUTCD calls for a 15' minimum clearance, but several states use a 17' minimum rule.

[M3019C LPS20]

The 15 ft. rule of thumb has been around for a long time.

[SignGeek101]

Never seen this before. Double red light.

[jakeroot]

Never seen this before. Double red light.

There's a lot of them in Alberta (chiefly Edmonton) where turns are protected-only, since so many of the turns are permissive (including a surprising amount of two-lane left turns).

[UCFKnights]

I guess you're allowed to turn left on red if one of the red bulbs burns out?

[thenetwork]

I guess you're allowed to turn left on red if one of the red bulbs burns out?

Or if it is a 4-segment signal...

[Mr. Matté]

There's a newly reconfigured traffic signal at the intersection of US 1 and CR 546/Bakers Basin Rd. in Lawrence Twp., NJ where the pedestrian countdown signals start the countdown (parallel to US 1) but at 0, the walk symbol returns for a few seconds and starts the countdown again. The countdown happens about three times before the US 1 signals actually change to yellow and the Bakers Basin traffic can proceed thereafter.

It's personally annoying for me since 100% of the time I'm on Bakers Basin/546, I'm on my bike and I use the time before the signals change to clip out, lower my glasses so they don't get fogged up, etc. When the cross street goes yellow, that's when I start my sequence to get ready to pedal hard across there. Is there some kind of actual statement that bans this in the MUTCD or any other official document that I can cite before sending the report out to DOT? I don't want to make this solely a convenience report to them. (not that it actually matters since they never respond even when I include my email and and I've stated before, one problem remained unfixed until I wrote my state legislator)

[US71]

Never seen this before. Double red light.

Texas uses them on their Left Turn Signals

[jeffandnicole]

There's a newly reconfigured traffic signal at the intersection of US 1 and CR 546/Bakers Basin Rd. in Lawrence Twp., NJ where the pedestrian countdown signals start the countdown (parallel to US 1) but at 0, the walk symbol returns for a few seconds and starts the countdown again. The countdown happens about three times before the US 1 signals actually change to yellow and the Bakers Basin traffic can proceed thereafter.

It's personally annoying for me since 100% of the time I'm on Bakers Basin/546, I'm on my bike and I use the time before the signals change to clip out, lower my glasses so they don't get fogged up, etc. When the cross street goes yellow, that's when I start my sequence to get ready to pedal hard across there. Is there some kind of actual statement that bans this in the MUTCD or any other official document that I can cite before sending the report out to DOT? I don't want to make this solely a convenience report to them. (not that it actually matters since they never respond even when I include my email and and I've stated before, one problem remained unfixed until I wrote my state legislator)

I saw this on US 130 at Browning Rd in Bellmawr one day. At least here, the signal length is dictated by a collective network of sensors determining when to change the light.  I figured that when the countdown reached to 0, there will still too much traffic approaching, and reset the ped to a walk phase and another countdown phase.

In my case above, I saw it occur once. Other times, either the walk signal never activated, or it only counted down once, and the light cycled soon after that.

If it's occurring every time the way you mentioned, there may be some sort of issue. But otherwise, the light is probably programmed to sense traffic coming from longer distances, and as above, if traffic is too heavy the light will remain green.  You'll have to go thru during slower period of traffic to determine if there's truly a problem.  I don't think there's any problems regarding the MUTCD .

[thenetwork]

There's a newly reconfigured traffic signal at the intersection of US 1 and CR 546/Bakers Basin Rd. in Lawrence Twp., NJ where the pedestrian countdown signals start the countdown (parallel to US 1) but at 0, the walk symbol returns for a few seconds and starts the countdown again. The countdown happens about three times before the US 1 signals actually change to yellow and the Bakers Basin traffic can proceed thereafter.

It's personally annoying for me since 100% of the time I'm on Bakers Basin/546, I'm on my bike and I use the time before the signals change to clip out, lower my glasses so they don't get fogged up, etc. When the cross street goes yellow, that's when I start my sequence to get ready to pedal hard across there. Is there some kind of actual statement that bans this in the MUTCD or any other official document that I can cite before sending the report out to DOT? I don't want to make this solely a convenience report to them. (not that it actually matters since they never respond even when I include my email and and I've stated before, one problem remained unfixed until I wrote my state legislator)

It could be that the pedestrian activation button for the crosswalk is not working properly or broken.  That is happened a few times in my town, resulting in the countdown timer and the WALK/DON'T WALK signal recycling 2-3 times until the actual traffic light changes for drivers.  If the light only changes on the side street when a vehicle is detected, then the crosswalk recycling will continue ad nauseum until the light does need to change for the waiting vehicle(s) on the side street.

On the other side of the coin, if there is a broken crosswalk activation button for the side street to cross the primary street, that will usually result in the side street getting a green on a regular and full-length basis with or without any vehicles &/or pedestrians waiting -- A big Pain In The Ass when the side street's green is only long enough for the waiting vehicle(s) if the signal system is working properly and there is no crosswalk traffic, but goes to a full 20-30+ second cycle if the crosswalk is activated (or broken).

[Mr. Matté]

If it's occurring every time the way you mentioned, there may be some sort of issue. But otherwise, the light is probably programmed to sense traffic coming from longer distances, and as above, if traffic is too heavy the light will remain green.  You'll have to go thru during slower period of traffic to determine if there's truly a problem.

I saw this happen this morning at about 9:00 AM, and saw it last weekend on Saturday morning as well so traffic was light in all directions. In this morning's instance though, all three of the turning lanes were filled so it wasn't a case of the sensors seeing a car and then the car going away.