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Traffic signal

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

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1995hoo

Quote from: realjd on July 11, 2013, 12:41:59 PM
....

If you really want to talk about unusual signal uses, check out this intersection from Fort Myers that has a separate pair of signal heads for each lane:

http://goo.gl/maps/90TYk

EDIT: Fixed link for Fort Myers signal. The old link pointed in the wrong direction.

We pass through that one frequently when we visit our relatives down there (we usually stay at the beach and they live off Briarcliff Road). I've never been able to understand why that light was set up that way, especially given that the one on the right seems to operate on a different cycle from the others. Do you have any idea why it's like that? Even on our very first visit I quickly got in the habit of making sure to move left as I approach that light.
"You know, you never have a guaranteed spot until you have a spot guaranteed."
—Olaf Kolzig, as quoted in the Washington Times on March 28, 2003,
commenting on the Capitals clinching a playoff spot.

"That sounded stupid, didn't it?"
—Kolzig, to the same reporter a few seconds later.


1995hoo

BTW, speaking about the green arrow lights for the thru lanes that never get a red, we have this slightly odd one on Commerce Street in Springfield, Virginia. What makes it odd is the doghouse signal for the left-turn lane onto the ramp to I-495. In theory, the doghouse should be unnecessary because there should never be a red light for the thru lane there–either the green left-turn arrow is on when someone trips the signal or it's not on–so the signal ought to be a dedicated signal for the left-turn lane. But because they wanted a permissive green, they used the doghouse style. This seems like a spot where a flashing yellow arrow would be a better solution.

http://goo.gl/maps/hhoOG
"You know, you never have a guaranteed spot until you have a spot guaranteed."
—Olaf Kolzig, as quoted in the Washington Times on March 28, 2003,
commenting on the Capitals clinching a playoff spot.

"That sounded stupid, didn't it?"
—Kolzig, to the same reporter a few seconds later.

Big John

^^  In Wisconsin, the common practice is to still use a 3-section RYG signal head for the through lanes, even though the red indication will never be used and the yellow used only if it ever goes into flash mode.  So it stays on as a solid green circular ball for most/all the time.  For the lest turn-movement it is either a a 3-section arrow for left on green arrow only movement or a 5-section tower if it is a permitted/protected movement, again with the red and yellow being as previously said.  Not sure if they changed that part to a FYA for any new/reconstructed instillations.

realjd

Quote from: 1995hoo on July 12, 2013, 10:51:40 AM
Quote from: realjd on July 11, 2013, 12:41:59 PM
....

If you really want to talk about unusual signal uses, check out this intersection from Fort Myers that has a separate pair of signal heads for each lane:

http://goo.gl/maps/90TYk

EDIT: Fixed link for Fort Myers signal. The old link pointed in the wrong direction.

We pass through that one frequently when we visit our relatives down there (we usually stay at the beach and they live off Briarcliff Road). I've never been able to understand why that light was set up that way, especially given that the one on the right seems to operate on a different cycle from the others. Do you have any idea why it's like that? Even on our very first visit I quickly got in the habit of making sure to move left as I approach that light.

The signal is set up that way to help with the merge on the bridge approach. Traffic gets absolutely horrendous during the tourist season.

dfnva

Quote from: 1995hoo on July 12, 2013, 11:42:39 AM
BTW, speaking about the green arrow lights for the thru lanes that never get a red, we have this slightly odd one on Commerce Street in Springfield, Virginia. What makes it odd is the doghouse signal for the left-turn lane onto the ramp to I-495. In theory, the doghouse should be unnecessary because there should never be a red light for the thru lane there–either the green left-turn arrow is on when someone trips the signal or it's not on–so the signal ought to be a dedicated signal for the left-turn lane. But because they wanted a permissive green, they used the doghouse style. This seems like a spot where a flashing yellow arrow would be a better solution.

http://goo.gl/maps/hhoOG

Here is a similar situation just to the north in Annandale, VA -- http://goo.gl/maps/PGTjh -- a 4-light tower instead of a doghouse for protective/permissive. Not sure what the top light is in either the 4-light or 2-light signal. Presumably, both would be green all the time since traffic on Maple Place can only turn right on Annandale Rd.

Big John

Quote from: dfnva on July 14, 2013, 05:08:08 PM
sure what the top light is in either the 4-light or 2-light signal. Presumably, both would be green all the time since traffic on Maple Place can only turn right on Annandale Rd.

It appears to be a yellow signal for if/when the signals go into flash mode.

xcellntbuy

Below is a link to an article on the front page of the July 15, 2013 edition of the South Florida Sun-Sentinel on the latest standards to provide hurricane-resistance to span-wire traffic signals that still predominate in Broward and Palm Beach Counties, as well as other parts of Florida.

http://www.sun-sentinel.com/news/palm-beach/fl-traffic-signals-retrofit-hurricanes-20130709,0,6351131.story

dfnva

Quote from: xcellntbuy on July 15, 2013, 05:09:10 AM
Below is a link to an article on the front page of the July 15, 2013 edition of the South Florida Sun-Sentinel on the latest standards to provide hurricane-resistance to span-wire traffic signals that still predominate in Broward and Palm Beach Counties, as well as other parts of Florida.

http://www.sun-sentinel.com/news/palm-beach/fl-traffic-signals-retrofit-hurricanes-20130709,0,6351131.story

Very interesting. I do find it interesting that a wind and hurricane-prone state like Florida (as well as others in the Southeast) still install span-wire signals while here in Virginia, most new installations are mast arms, which, over the past 20 years, have replaced a great majority of older span wire installations.

realjd

Quote from: xcellntbuy on July 15, 2013, 05:09:10 AM
Below is a link to an article on the front page of the July 15, 2013 edition of the South Florida Sun-Sentinel on the latest standards to provide hurricane-resistance to span-wire traffic signals that still predominate in Broward and Palm Beach Counties, as well as other parts of Florida.

http://www.sun-sentinel.com/news/palm-beach/fl-traffic-signals-retrofit-hurricanes-20130709,0,6351131.story

Here's a link to a copy of the article that isn't behind a paywall: http://www.orlandosentinel.com/news/local/orange/fl-traffic-signals-retrofit-hurricanes-20130709,0,6417825.story

roadman65

http://www.flickr.com/photos/22306412@N07/9120682662/in/photostream/
This signal looks a little strange with the heads mounted in different positions on the mast arm.  Obviously the contractor was in a hurry and does not care about looks!
Every day is a winding road, you just got to get used to it.

Sheryl Crowe

M3019C LPS20

This two-section (red and green) pedestrian signal from the Ruleta company still remains in existence in the city of New York. It is in Central Park, and it is likely the last of its kind there. I visited it in person last week.










brickbuilder711

Quote from: realjd on July 16, 2013, 02:33:06 PM
Quote from: xcellntbuy on July 15, 2013, 05:09:10 AM
Below is a link to an article on the front page of the July 15, 2013 edition of the South Florida Sun-Sentinel on the latest standards to provide hurricane-resistance to span-wire traffic signals that still predominate in Broward and Palm Beach Counties, as well as other parts of Florida.

http://www.sun-sentinel.com/news/palm-beach/fl-traffic-signals-retrofit-hurricanes-20130709,0,6351131.story

Here's a link to a copy of the article that isn't behind a paywall: http://www.orlandosentinel.com/news/local/orange/fl-traffic-signals-retrofit-hurricanes-20130709,0,6417825.story

Interesting find. Meanwhile along 8th street and Crandon Blvd in Miami according to Street View looks like Miami-Dade has already done this retrofit to those intersections.

froggie

#362
Jumping in a bit late here...regarding overhead and side-mounted signals, I come from a state that does both extensively (Minnesota).  Really helps with visibility and agree that it should be emulated more across the country.

Regarding span-wire signals, it's not just Florida....the southeastern states as a general rule use span-wire signals as a standard...Mississippi, Louisiana, Alabama, Georgia, South Carolina, North Carolina....all states that fall in the "hurricane belt" as well.  Though Mississippi has *SLOWLY* started to come around to mast-arm signals, at least along the Gulf Coast and in a few cities (namely Hattiesburg....Meridian has long had mast-arm signals).  Presumably, span-wire is cheaper to install.

PColumbus73

I was wondering, is there any other state that uses this setup for left turn signals

https://maps.google.com/maps?hl=en&ie=UTF8&ll=33.71364,-78.899787&spn=0.000967,0.001206&t=h&z=20&vpsrc=6&cbll=33.713758,-78.89984&panoid=zK0BGuW0GZPWsPopsapRDQ&cbp=12,78.3,,2,-5&ei=XbhIUs-hJ9L_xQGV6YG4Cg&pw=2

South Carolina uses them extensively, and I've heard/seen them used in parts of Maryland and Texas. Any other place where they are used?

kj3400

Quote from: PColumbus73 on September 29, 2013, 07:44:11 PM
I was wondering, is there any other state that uses this setup for left turn signals

https://maps.google.com/maps?hl=en&ie=UTF8&ll=33.71364,-78.899787&spn=0.000967,0.001206&t=h&z=20&vpsrc=6&cbll=33.713758,-78.89984&panoid=zK0BGuW0GZPWsPopsapRDQ&cbp=12,78.3,,2,-5&ei=XbhIUs-hJ9L_xQGV6YG4Cg&pw=2

South Carolina uses them extensively, and I've heard/seen them used in parts of Maryland and Texas. Any other place where they are used?

Maryland's is more like http://goo.gl/maps/Z4y2P
Call me Kenny/Kenneth. No, seriously.

US71

Quote from: PColumbus73 on September 29, 2013, 07:44:11 PM
I was wondering, is there any other state that uses this setup for left turn signals

https://maps.google.com/maps?hl=en&ie=UTF8&ll=33.71364,-78.899787&spn=0.000967,0.001206&t=h&z=20&vpsrc=6&cbll=33.713758,-78.89984&panoid=zK0BGuW0GZPWsPopsapRDQ&cbp=12,78.3,,2,-5&ei=XbhIUs-hJ9L_xQGV6YG4Cg&pw=2

South Carolina uses them extensively, and I've heard/seen them used in parts of Maryland and Texas. Any other place where they are used?

I've seen that once or twice in Louisiana along US 80.
Like Alice I Try To Believe Three Impossible Things Before Breakfast

mapman1071

Quote from: M3019C LPS20 on July 26, 2013, 09:25:22 PM
This two-section (red and green) pedestrian signal from the Ruleta company still remains in existence in the city of New York. It is in Central Park, and it is likely the last of its kind there. I visited it in person last week.











You can also find these signals under the El along Liberty Avenue In Ozone Park East of Rockaway Blvd and at Liberty Avenue & 133rd Street.
Also along Shore Front Parkway In The Rockaway's (They may or may not be standing due to Sandy damage.)

Alps

Quote from: mapman1071 on September 30, 2013, 02:22:50 PM
You can also find these signals under the El along Liberty Avenue In Ozone Park East of Rockaway Blvd and at Liberty Avenue & 133rd Street.
Also along Shore Front Parkway In The Rockaway's (They may or may not be standing due to Sandy damage.)
Shore Front Pkwy. signals were gone years ago.

getemngo

Today I came across this at the end of an exit ramp and took a crappy cell phone photo (eastbound I-96 at exit 38, to be specific).



There are indeed 4 lanes: a left turn lane, a left/thru lane, and two right turn lanes. It's a split phase signal 24 hours a day, so everything you see gets a green at the same time, then opposing traffic has a green. I'm pretty sure the sign on the right lights up with "NO TURN ON RED" when opposing traffic has a green - those pop up in Michigan from time to time.

So there's one signal for each lane, and all the turn movements are covered. I understand what they were trying for, but many things about it look incredibly... off.

  • A protected left turn signal next to a doghouse left signal. I would hate to see a simultaneous green ball and red arrow, or for that arrow to be flashing. X-( Thank goodness they're always both green and both red at the same time... but now they can't change the phasing without reinstalling half the signal.
  • Going straight through is a legal move, but there is only one green ball for the whole assembly.
  • A right turn on red is presumably allowed, despite the red arrows (since it only says NO TURN ON RED at certain times). MDOT has always treated a red right arrow like a red ball the few times I've seen them.

Are any of these, or anything else, MUTCD violations?
~ Sam from Michigan

Big John

^^ The way you describe the intersection, the doghouse signal should be a 4-section signal instead - R-Y-G-GA.  No need for a redundant yellow arrow on a split phase. 

The part I am not clear on is whether the far left signal satisfies the 2-primary-signal requirement with the adjacent signal.

Alex4897

How not to use a doghouse signal, by DelDOT.
DE 1 south offramp to DE 299.  I believe they meant to use an upside down T signal here, which'd be practically useless also considering nearly nobody is going to get off then get back on the freeway. (barring some disaster within the interchange or something)

https://maps.google.com/?ll=39.454728,-75.676924&spn=0.000954,0.002064&t=h&z=20&layer=c&cbll=39.454728,-75.676924&panoid=zWqarsSk-RxUjuW-LEezdQ&cbp=12,163.82,,0,1.46
👉😎👉

M3019C LPS20

Quote from: mapman1071 on September 30, 2013, 02:22:50 PM
You can also find these signals under the El along Liberty Avenue In Ozone Park East of Rockaway Blvd and at Liberty Avenue & 133rd Street.
Also along Shore Front Parkway In The Rockaway's (They may or may not be standing due to Sandy damage.)


The last handful of survivors that were in existence in certain areas of Queens, such as Richmond Hill and the Rockaways, retired from useful service in the late 2000s. Around 2007 or so. What replaced them were mainly 8" three-section traffic signals from General Traffic Equipment, and the ones in the Far Rockaways didn't survive tropical storm Sandy.

NYhwyfan

Quote from: Big John on October 01, 2013, 10:56:38 PM
^^ The way you describe the intersection, the doghouse signal should be a 4-section signal instead - R-Y-G-GA.  No need for a redundant yellow arrow on a split phase. 

The part I am not clear on is whether the far left signal satisfies the 2-primary-signal requirement with the adjacent signal.

I agree that a four-section would have been sufficient, however maybe their reasoning was concern for signal height

Big John

#373
Quote from: NYhwyfan on October 07, 2013, 04:26:14 PM
Quote from: Big John on October 01, 2013, 10:56:38 PM
^^ The way you describe the intersection, the doghouse signal should be a 4-section signal instead - R-Y-G-GA.  No need for a redundant yellow arrow on a split phase. 

The part I am not clear on is whether the far left signal satisfies the 2-primary-signal requirement with the adjacent signal.

I agree that a four-section would have been sufficient, however maybe their reasoning was concern for signal height
If clearance was a concern, a permissible signal arrangement can be an "inverted T" with a red on top, yellow in the middle, and the bottom row having 2 signal heads, a green left arrow and a green ball, with the bottom row being centered with the center of the red and yellow balls.

legal arrangements: http://mutcd.fhwa.dot.gov/htm/2009/part4/fig4d_11_longdesc.htm

roadman65

Every day is a winding road, you just got to get used to it.

Sheryl Crowe



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