being a good neighbor--

[RadarTech]

Optical pre-emption. Fact. A digitaly encripted infered signal transmitted to the signal alerts it that an emergency vehicle is approaching. The signal has rules it has to follow before it can give the green light to the emergency vehicle though. For example: if a "Walk" signal is active the other direction, the signal will terminate the walk, but it must give the full time for pedestrian clearance before it can give the emergency vehicle the green light and turn all opposing directions red.

yeppers.. lots o legal ideas in there...
And I bet it is a touchy subject for that timing too!

J

 

[dcyrilc]

Optical pre-emption. Fact. A digitaly encripted infered signal transmitted to the signal alerts it that an emergency vehicle is approaching. The signal has rules it has to follow before it can give the green light to the emergency vehicle though. For example: if a "Walk" signal is active the other direction, the signal will terminate the walk, but it must give the full time for pedestrian clearance before it can give the emergency vehicle the green light and turn all opposing directions red.

All current signals also have a device called a "Conflict Monitor" which monitors proper operation of the signal and is capable of putting the signal into flash if a fault is observed. We often have to go to a signal where there has been an accident and both parties claim to have had a green light and do what we call conflicting the signal. We manually place a bad output for every operation of the signal and comfirm that the conflict monitor puts the signal into flash. By doing this we confirm that the signal could not have had two conflicting green lights operating and remove any liability from the city for a faulty signal. Two seperate devices have to fail for this to be possible, but the city policy is to test it every time.

 

[dcyrilc]

yeppers.. lots o legal ideas in there...
And I bet it is a touchy subject for that timing too!

J

Although timing and operational parameters are determined by the engineers, I personally don't like having walks come up without requiring the button to be pushed. It slows down the ability of the signal to respond to emergency vehicles.

 

[RadarTech]

All current signals also have a device called a "Conflict Monitor" which monitors proper operation of the signal and is capable of putting the signal into flash if a fault is observed. We often have to go to a signal where there has been an accident and both parties claim to have had a green light and do what we call conflicting the signal. We manually place a bad output for every operation of the signal and comfirm that the conflict monitor puts the signal into flash. By doing this we confirm that the signal could not have had two conflicting green lights operating and remove any liability from the city for a faulty signal. Two seperate devices have to fail for this to be possible, but the city policy is to test it every time.

yea I see the legal issues here...

anyway--- I have always found the PLC with the ladder logic interesting to work on.. course it has been nearly 12 years since I even looked at one...


J

 

[dave1949]

Although timing and operational parameters are determined by the engineers, I personally don't like having walks come up without requiring the button to be pushed. It slows down the ability of the signal to respond to emergency vehicles.

One of my pet peeves - a pedestrian who automatically pushes the crosswalk button, then proceeds to cross without waiting. Eventually brings the whole intersection to a halt for a phantom walker who is 1/2 a block down the street by then. They should be whipped
Dave.

 

[RadarTech]

One of my pet peeves - a pedestrian who automatically pushes the crosswalk button, then proceeds to cross without waiting. Eventually brings the whole intersection to a halt for a phantom walker who is 1/2 a block down the street by then. They should be whipped
Dave.

yea.. but what about the fool that walks across in the middle of the street without the walk button and ready befuddles traffic!!!!


J

 

[dcyrilc]

One of my pet peeves - a pedestrian who automatically pushes the crosswalk button, then proceeds to cross without waiting. Eventually brings the whole intersection to a halt for a phantom walker who is 1/2 a block down the street by then. They should be whipped
Dave.

Mine too. We have a couple of locations where the signal is for a pedistrian trail crossing and peds do that all the time. I hate it.

 

[dcyrilc]

Mine too. We have a couple of locations where the signal is for a pedistrian trail crossing and peds do that all the time. I hate it.

The one I really don't understand though is when people cross the street 25 feet from the crosswalk and have small children with them.:confused2: What are they teaching their kids?

 

[HeyNow]

Back on topic....I need more feel good stories.

 

[RadarTech]

Back on topic....I need more feel good stories.

ABSOLUTELY!!!

And as the OP...
I Second that motion....


Jerry