Red and Green?

[Amtrakprod]

I was at this light today, one that I know has this strange phase. The normal green ball and green right arrow occurs, but seconds later, the right arrow and right turn signals go yellow and then red. The doghouse shows both the green ball and red ball. This happens for no apparent reason! I'll try to get better pics soon!


iPhone

[ET21]

Is the green ball light aimed at a different intersection? It looks like it's on an angle compared to the red light right above it

[roadfro]

I was at this light today, one that I know has this strange phase. The normal green ball and green right arrow occurs, but seconds later, the right arrow and right turn signals go yellow and then red. The doghouse shows both the green ball and red ball. This happens for no apparent reason! I'll try to get better pics soon!

Can you link a map location so we can get some more context?

[Amtrakprod]

Is the green ball light aimed at a different intersection? It looks like it's on an angle compared to the red light right above it

It's a 3 way intersection. Here's the link https://goo.gl/maps/U6kzzTYwqKEyi35X8


iPhone

[Amtrakprod]

Also fun fact. When this signal was first installed the 4 section left turn signal on the main Trapelo road was mounted on the bottom right of the pole, and the top two signals were 3 sections. It was fixed quickly I guess


iPhone

[jakeroot]

Is the green ball light aimed at a different intersection? It looks like it's on an angle compared to the red light right above it

It's a 3 way intersection. Here's the link https://goo.gl/maps/U6kzzTYwqKEyi35X8

It would appear that red arrows would be a wise replacement for those circular red indications.

The way I understand it, the doghouse is a near-side signal for both the left and right turns. But both maneuvers, which apparently go at different times, both seem to use circular-only indications (or possibly, the right turn only uses a green arrow). Easy fix would be to replace the right turn red indications with red arrows. The doghouse would have a right red arrow, with two right-facing amber and green arrows below that on the right; two regular amber and green circular indications on the bottom left.

[roadfro]

I think there's no reason to have the doghouse signal there to repeat both left and right turns, since the right turn signal displays are well within line of sight and are very close to the two primary signals for the right turn. Should've just installed it as a repeater for the left turns and called it a day.

Also interesting when I looked at the intersection in Street View: There appear to be signals facing the residential driveways across the street.

[Brandon]

I was at this light today, one that I know has this strange phase. The normal green ball and green right arrow occurs, but seconds later, the right arrow and right turn signals go yellow and then red. The doghouse shows both the green ball and red ball. This happens for no apparent reason! I'll try to get better pics soon!

Looking at the photo and looking at the intersection on Google Street View, it seems bizarre that the green would be on for the left turn at the same time as a red for the right turn.  I could understand the other way (red for left, green for right), but this way (red for right, green for left) has no known reason for being.  There is no obvious conflict, with the left turn having a green due to the setup of the intersection, for the right turn.

[paulthemapguy]

I would just replace all the yellow and green signal sections protecting a left turn with left arrows.  Leave the red signal as a ball.

[jakeroot]

I would just replace all the yellow and green signal sections protecting a left turn with left arrows.  Leave the red signal as a ball.

Again, you can't, because the left turn isn't protected.

[Amtrakprod]

I would just replace all the yellow and green signal sections protecting a left turn with left arrows.  Leave the red signal as a ball.

Again, you can't, because the left turn isn't protected.

Remove that doghouse, and put arrows on the right turn signals. Also check out some other trapelo road signals, (the main street), there are some weird setups with many high (way too high) cantilevers.

[jakeroot]

I would just replace all the yellow and green signal sections protecting a left turn with left arrows.  Leave the red signal as a ball.

Again, you can't, because the left turn isn't protected.

Remove that doghouse, and put arrows on the right turn signals. Also check out some other trapelo road signals, (the main street), there are some weird setups with many high (way too high) cantilevers.

That would be fine too. Keep the near-side signal on the edge of that porkchop island for the left turn, but maybe eliminate the near-side right turn signal.

I've also drawn this, where the right turn signal becomes a HAWK which normally operates as a yield:

[Amtrakprod]

I would just replace all the yellow and green signal sections protecting a left turn with left arrows.  Leave the red signal as a ball.

Again, you can't, because the left turn isn't protected.

Remove that doghouse, and put arrows on the right turn signals. Also check out some other trapelo road signals, (the main street), there are some weird setups with many high (way too high) cantilevers.

That would be fine too. Keep the near-side signal on the edge of that porkchop island for the left turn, but maybe eliminate the near-side right turn signal.

I've also drawn this, where the right turn signal becomes a HAWK which normally operates as a yield:

What's with the upside down hawk


iPhone

[Brandon]

Looking at the photo and looking at the intersection on Google Street View, it seems bizarre that the green would be on for the left turn at the same time as a red for the right turn.  I could understand the other way (red for left, green for right), but this way (red for right, green for left) has no known reason for being.  There is no obvious conflict, with the left turn having a green due to the setup of the intersection, for the right turn.

In most states, it's not acceptable to have a slip lane with a green signal at the same time as oncoming permissive left turn.

For example, this right turn in Albuquerque: https://goo.gl/maps/amBwxn1rkcXJyNao9

There's no oncoming left turn here that is visible in the photo.  It's effectively a "T" intersection and this part is the "T".

[jakeroot]

What's with the upside down hawk

Accident

Looking at the photo and looking at the intersection on Google Street View, it seems bizarre that the green would be on for the left turn at the same time as a red for the right turn.  I could understand the other way (red for left, green for right), but this way (red for right, green for left) has no known reason for being.  There is no obvious conflict, with the left turn having a green due to the setup of the intersection, for the right turn.

In most states, it's not acceptable to have a slip lane with a green signal at the same time as oncoming permissive left turn.

For example, this right turn in Albuquerque: https://goo.gl/maps/amBwxn1rkcXJyNao9

There's no oncoming left turn here that is visible in the photo.  It's effectively a "T" intersection and this part is the "T".

The driveways have signals. Note the signals facing away from the left turn stop line.

[Amtrakprod]

Let's extend this even more. One intersection down is a common New England Red and Green, and a notably high cantilever for no reason: https://www.google.com/maps/@42.3880433,-71.1910772,3a,75y,173.41h,85.56t/data=!3m6!1e1!3m4!1s4ivEC0C9eE3anLaL7Zq7mw!2e0!7i13312!8i6656

[deathtopumpkins]

Let's extend this even more. One intersection down is a common New England Red and Green, and a notably high cantilever for no reason: https://www.google.com/maps/@42.3880433,-71.1910772,3a,75y,173.41h,85.56t/data=!3m6!1e1!3m4!1s4ivEC0C9eE3anLaL7Zq7mw!2e0!7i13312!8i6656

That mast arm on the left is high in order to be above the trolleybus wires.

[Brandon]

What's with the upside down hawk

Accident

Looking at the photo and looking at the intersection on Google Street View, it seems bizarre that the green would be on for the left turn at the same time as a red for the right turn.  I could understand the other way (red for left, green for right), but this way (red for right, green for left) has no known reason for being.  There is no obvious conflict, with the left turn having a green due to the setup of the intersection, for the right turn.

In most states, it's not acceptable to have a slip lane with a green signal at the same time as oncoming permissive left turn.

For example, this right turn in Albuquerque: https://goo.gl/maps/amBwxn1rkcXJyNao9

There's no oncoming left turn here that is visible in the photo.  It's effectively a "T" intersection and this part is the "T".

The driveways have signals. Note the signals facing away from the left turn stop line.

If the driveways are green, then the left turn should be red (for the same reason as the right turn), based on the location of the driveways.
https://goo.gl/maps/yCNyoK28e6zVv7JXA

[Brandon]

Let's extend this even more. One intersection down is a common New England Red and Green, and a notably high cantilever for no reason: https://www.google.com/maps/@42.3880433,-71.1910772,3a,75y,173.41h,85.56t/data=!3m6!1e1!3m4!1s4ivEC0C9eE3anLaL7Zq7mw!2e0!7i13312!8i6656

That would make more sense as a five-lamp tower if it displays a red ball and a green arrow.

[Amtrakprod]

Also that 4 section left turn at Pleasant/Trapelo doesn't even have a bi-model arrow.

[jakeroot]

Looking at the photo and looking at the intersection on Google Street View, it seems bizarre that the green would be on for the left turn at the same time as a red for the right turn.  I could understand the other way (red for left, green for right), but this way (red for right, green for left) has no known reason for being.  There is no obvious conflict, with the left turn having a green due to the setup of the intersection, for the right turn.

In most states, it's not acceptable to have a slip lane with a green signal at the same time as oncoming permissive left turn.

For example, this right turn in Albuquerque: https://goo.gl/maps/amBwxn1rkcXJyNao9

There's no oncoming left turn here that is visible in the photo.  It's effectively a "T" intersection and this part is the "T".

The driveways have signals. Note the signals facing away from the left turn stop line.

If the driveways are green, then the left turn should be red (for the same reason as the right turn), based on the location of the driveways.
https://goo.gl/maps/yCNyoK28e6zVv7JXA

I thought about that too. The offsets would be unusual for a "yield on green" signal, but they did remove a fourth southerly-facing signal for one of the driveways (current image), which makes me wonder if all of the driveways and the left turn go at once (why else would they remove one of the two signals required for each approach?). If this is not the case, sure, change the left turn to green arrows. But the signals facing the driveways should have arrows as well, since it's all split-phased.

[Amtrakprod]

Strange thing to do, but maybe I'll go and u turn in a driveway to see what happens! 

[jakeroot]

Strange thing to do, but maybe I'll go and u turn in a driveway to see what happens! 

Easiest thing is just to look back at the lights facing the driveway when you turn left. If they're all red, the intersection is split-phased and could be modified with green arrows.

[Amtrakprod]

Strange thing to do, but maybe I'll go and u turn in a driveway to see what happens! 

Easiest thing is just to look back at the lights facing the driveway when you turn left. If they're all red, the intersection is split-phased and could be modified with green arrows.

I already know that the driveway lights aren't green as the other street has a green. That's also proven because there are sensors for those driveways. It's def split phasing.


iPhone

[jakeroot]

Strange thing to do, but maybe I'll go and u turn in a driveway to see what happens! 

Easiest thing is just to look back at the lights facing the driveway when you turn left. If they're all red, the intersection is split-phased and could be modified with green arrows.

I already know that the driveway lights aren't green as the other street has a green. That's also proven because there are sensors for those driveways. It's def split phasing.

Oh. Well then green arrows would work fine for that left turn. My whole point has been that the intersection must use permissive phasing because there are no green arrows for the left turn. Older intersections sometimes would split-phase without any green arrows, but I was not aware of new intersections that operated that way.

I normally could have figured this out on my own if I was able to find a street view image with the left turn being green, but I wasn't able to.