Strange traffic light paradox

[al78]

Currently in Horsham they have been doing some gas main work on the A281 from the eastern edge of town all the way across to the western edge, working their way along. This has required the use of temporary traffic lights. This has been going on for about a couple of months now and as the road in question is my primary route into town I go past these roadworks very regularly. The one thing I have noticed is that when approaching the temporary lights the number of times the light is red is vastly greater than the number of times the light is green, by my estimate at least a factor of 10. Assuming that I approach the lights at a random point in their sequence it seems to me that I should get far more green lights than I am actually getting. I wouldn't expect the green to red ratio to be as high as 50% as there are periods where both lights are red to give traffic enough time to clear the roadworks but <10% seems far less than I would expect. Have I missed something obvious here?

 

[daSmirnov]

A lot of the times the lights have been setup to handle multiple roads. I know the lights over on the eastern edge of town are controlling 4 ways. Recently on the western side of town they've been setup 3 ways, and as they've worked their way along from Brighton road they've been set up 4 ways on some stretches like Albion Way.

Also noticed I always get a red light. Bypassed them last night or the night before by using the shared-use pavement, not something I recommend at night, full of crap.

 

[betty swollocks]

Most modern lights have movement sensors and are by default red from all directions and will turn green for whichever direction senses traffic movement first.
At least that's the theory as I understand it.

 

[summerdays]

Most modern lights have movement sensors and are by default red from all directions and will turn green for whichever direction senses traffic movement first.
At least that's the theory as I understand it.

I think that is right. I've also been told that the lights can get themselves very muddled if people keep jumping them.

 

[Miquel In De Rain]

The Harrow Green lights are my least favourite lights and generally almost always catch me.So bad in fact I tend to avoid them if poss by cycling down the Leytonstone backstreets.They even used to catch me at 3am.Waiting there like a lemon.

It's funny but due to sods law after I moved I tended to inherit this set of lights as opposed to all the sets down the Leyton High Road on my old commute.

Oh yeah,they are so bad even Mr Beemer got out of his car today to have a go at someone blocking the traffic (before he got caught on another long phase).

 

[Svendo]

I think that is right. I've also been told that the lights can get themselves very muddled if people keep jumping them.

Some will still have a cycle, but interrupt it when motion is detected. Quite a few lights, especially filters with their own lanes, will be detection only around Rochdale, which is frustrating when there are no cars going your way and your bike doesn't activate the loops in the road .

 

[Miquel In De Rain]

Some will still have a cycle, but interrupt it when motion is detected. Quite a few lights, especially filters with their own lanes, will be detection only around Rochdale, which is frustrating when there are no cars going your way and your bike doesn't activate the loops in the road .

I had a problem with a set at Stratford,not so much with the loop but with the camera thing not reacting to my lights,this went on for about two years.I dont use them now.Commute changed just over a year ago.

 

[summerdays]

Some will still have a cycle, but interrupt it when motion is detected. Quite a few lights, especially filters with their own lanes, will be detection only around Rochdale, which is frustrating when there are no cars going your way and your bike doesn't activate the loops in the road .

I've reported lights that I know don't react to the bike before now. And they were fixed eventually (took about a year though and more than one report).

 

[Svendo]

I've reported lights that I know don't react to the bike before now. And they were fixed eventually (took about a year though and more than one report).

The one I used to use regularly I didn't bother reporting as it also had toucan crossings, so I could do what's technically a RLJ and join the toucan crossing. I've moved now and don't go that way.

 

[Andrew_Culture]

I swear some of the sensors don't see you if you're on a bike, I've been sat at three way lights for several minutes before a car rolls up behind me and turns ours green.

The council here in Ippo are really receptive to cyclists making comment about light timings, there was one set of two lights about a hundred yards apart and a few cyclists emailed the council to say there wasn't enough time given by the lights for a cyclist to get safely from one set of lights to the other, so the council changed the timings!

 

[jdtate101]

Yep, one like that near me. I can sit there for 10mins like a complete numpty waiting for a car to come along and change the light. Not so bad in summer, but in winter it doesn't take long to cool down and get rally cold.

 

[summerdays]

You don't have to sit there for 10 mins - if it doesn't change for you, it's broken so proceed with care (baring in mind traffic from other directions doesn't know it's broken for you) or get off and walk across.

 

[al78]

Funnily enough, the day after I started this thread the roadworks had gone. They had been working their way along the A281 for over two months and I was wondering what they were going to do if they reached the junction with the bypass on the edge of town (which is grade separated).

 

[sidevalve]

I had a problem with a set at Stratford,not so much with the loop but with the camera thing not reacting to my lights,this went on for about two years.I dont use them now.Commute changed just over a year ago.

Where DID this fantasy about signals reacting to lights come from ? For once and for all, they do not react to lights. They react to movement [pole mounted detectors] or to metal mass [loops in road type]. If you are waiting for a filter arrow and it's got a loop [usually square] and you are on your own [no vehicles at all] stay ON the loop or it will ignore you and assume a random false "demand". Remember it works by induction so keep the biggest mass of metal [usually the BB & rear wheel] close to the loop [but still inside it].
One problem you may find is that a relatively little used filter will require several vehicles to be waiting before it triggers, [check how far back the loop is], this is not just a "go" at cyclists but an attempt to keep the main traffic flowing, after all you wouldn't want to be stopped six times when approaching a junction simply to let one car turn right.

 

[RedRider]

Where DID this fantasy about signals reacting to lights come from ? For once and for all, they do not react to lights. They react to movement [pole mounted detectors] or to metal mass [loops in road type]. If you are waiting for a filter arrow and it's got a loop [usually square] and you are on your own [no vehicles at all] stay ON the loop or it will ignore you and assume a random false "demand". Remember it works by induction so keep the biggest mass of metal [usually the BB & rear wheel] close to the loop [but still inside it].
One problem you may find is that a relatively little used filter will require several vehicles to be waiting before it triggers, [check how far back the loop is], this is not just a "go" at cyclists but an attempt to keep the main traffic flowing, after all you wouldn't want to be stopped six times when approaching a junction simply to let one car turn right.

Good info, potentially. How do you tell where the loop is, what does it look like please?
EDIT Oops, see this was answered recently in this thread