WORK THIS ONE OUT

[B.O.B DOLE]

20yards from traffic lights then they turn red, i am waiting in the
rat mobile for other traffic to come from the other road but nothing
next they turn to green traveled another 300 yards no traffic in front then 20 yards from lights they turn red and again no traffic from the other side.

when i had finished a few kills i was coming back the other way and quese what the lights turn RED and no traffic coming the other way this was happining all day. whats going on.

 

[Richardp]

Oh! so your ok then.

 

[B.O.B DOLE]

Oh! so your ok then.

mmmmmmmmmmmm not quite got the point dp

 

[Moz]

B.O.B DOLE

lights are bugg*red

 

[noodlz]

Were you in Babylon on a Friday night?

 

[gcol]

The lights are on a timer dude. Probably set by a woman.
Those sensors on the road don't ultimately dictate the traffic light changes.

 

[mlb3c]

The lights are on a timer dude. Probably set by a woman.
Those sensors on the road don't ultimately dictate the traffic light changes.

will I ever learn?

 

[gcol]

_____________________
Lynda, moderator

please note forum rule 20

 

[gcol]

Lynda, if you'd bothered to read the rest of the thread then you'd have realised that we were talking about traffic lights and I mentioned that they were probably set by women due to their total lack of common sense timing (a joke). I just happened to mention that the mod on this site (a woman) probably wouldn't like the comment and to wait and see what would happen. You've embarresed yourself by deleting it and saying that I was hijacking the post. How insecure you seem to be. I pity you.
________________________
Lynda, moderator

That was not the way it came across

 

[breezer]

The lights are on a timer dude. Probably set by a woman.
Those sensors on the road don't ultimately dictate the traffic light changes.

most traffic lights have an induction loop to detect the presence of actual traffic (some do have amicrowave detector to detect on coming traffic)

if the sensor fails, traffic lights will revert to a "timer"

also if too many people jump the lights (say a lorry has broken down and you have not a lot of choice) this "upsets" the traffic sensor and it thinks there is a lot of traffiic coming the other way, so it puts the other lights to red.

also most traffic lights can actually be controlled / over ridden from one central place.

traffic lights should not be confused with "pelican crossings" as these work differntly

 

[gcol]

What if there's loads of traffic waiting at each side of a junction? If there's a queue at each set of lights then the sensors in the road are useless. It's dictated by a timer set a different levels at different times of the day.

 

[breezer]

What if there's loads of traffic waiting at each side of a junction? If there's a queue at each set of lights then the sensors in the road are useless. It's dictated by a timer set a different levels at different times of the day.

fraid not.

timers are only used as a "oh dear the induction loop is not working" back up

the idea is (believe it or not) to keep traffic flowing not to hold it up, which is what timers were found to do.

A timer does not know / can not tell if there is any traffic present, so to run traffic lights on a timer is pointless (unless the induction loop has failed)

i would agree that when invented they did run on timers*, but now traffic lights are very highly advanced

also on a given road, area, all the traffic lights are often inter connected to keep traffic flowing. there is a famous one in London, its called the green wave. You must catch it right, but if you do , and you must drive @ exactly 30mph, you can drive a few miles (thats a lot in london) with out stopping because all the lights will be green by the time you get there.

another thing, in some boroughs, busses have priority and roadside sensors detect a buss approacing and change the lights in its favour.


*useless but true

1) The first set of traffic lights in the UK (maybe world) were operated by a police officer, they were some where near the hoses of parliment.

They were iluminated by a gas light, one day they blew up, killing the police officer operator

2) If you "jump" a set of lights which have a red light camera in order to make way for an emergency vehicle, Tough, you still get fined and or points.

 

[gcol]

The point I'm trying to make Breezer me owd chum, is that if there's two roads meeting to form a crossroad. Then what if there's say 400 yards of traffic at one and 200 yards at the other. The traffic lights don't have sensors that far back and that amount of traffic can't pass through in one go, so how do they know how to even the flow out if not for timers that are pre-set at proven settings for given traffic conditions found at certain times of the day?

 

[breezer]

they still use their induction loops.

yes thay are not that far back, but using your example, (assuming no more cars arrive at either side)

what would happen if you had a timer and the 200yds of traffic had gone?

it would still stop the remaining 200 yds(left from your 400 yds) to let through er, nothing (they have all gone, the 200yds worth of traffic)

That is exactly why they do use induction loops or microwaves to prevent them from going green when there is no traffic

dont get me wrong, their is a timer to detrmine the length of a phase, but it is controlled by the induction loop or microwave. and yes they do fail sometimes so they will run soley on a timer, but 99% of the time its now induction loop or microwave or UTC (urban traffic control)

 

[empip]

In Saudi there exists lights with 'seconds' count down to next change displayed.