Yer know - the black ones, usually come in pairs with a box chained to a lamp post ?

I think they are there to count volumes of traffic - nothing to do with speed

might be wrong though

Jon

It's merely traffic monitoring. If however you see three cables then watch your speed because that will be a DS2 Truvelo (speed trap).

The 2 cable ones also measure speed(but not accuratley enough to do you) so slow down when you come up to them. I used to go over them about 5Mph(when appropriate) just to skew the average speeds.

The theory being, that the data they gather will be used to work out if the speed limit is correct for the traffic levels and road. Go over too fast and they start to put in traffic calming/cameras and may even lower the limit. If the average speed is below the limit then they'll leave things as they are..

Pnumatic traffic flow counters..
Bob (ex Notts C.C. trafic signal engineer)

(you beat me to it Neil!)

[Edited by Active - 8/24/2002 9:12:17 AM]

Bob,

does this mean that they stop working if the air filled tubes get punctured?

I've seen them get detroyed completely on roads used by heavy wagons (less it's kids...or Neil :p )

Jon

I never broke any. Just went over them really slow so as to mess up the average speed readings.

Vandals break them by slipping the clutch and wheel spinning over them. My acts of rebellion were much less harmful and more insidious

ditto above aways go slow over them

If you go over the cables on a bike and drag the back brake to the point of semi-lockup, you can rip the cables out of their securings.
Not that I've done this of course.
Well only on my own private road anyway ;-)

Wouldnt it be easier to nick the box with a pair of bolt cutters ;)

I wasnt sure what they were up to now, but I know they stretch a long way on the tow bar on a 4x4 doing a standing start :D ...

Nath

Yes they are totally harmless... only primeraly intended for traffic surveys by the local authorities. Usually used on primary routes to constantly update traffic flows. They can be ordered by the traffic management department of the local authority from the data collection dept of the same authority, (different dept).
The data collected could be used, and is on occations for the justification for traffic calming. Usually requested by the local residents, Parish councils etc. The information gathered is often used as well to REFUSE traffic calming measures by those that had requested them in the first place.
Hope this explains things a little better.
Bob
They are no way used for entrapment of the motorist.


[Edited by Active - 8/25/2002 10:16:37 AM]

So their appearance a week before an almost daily police speed trap on this stretch of road is pure coincidence ?

Oh and why would there be two sets of these cables (and two boxes) on the same road, around quarter of a mile between them - only turn offs from this road are into residential estates.

V suspicious....

[Edited by Riftzone - 8/25/2002 7:47:23 AM]

Possibly local residents have complained of speeding traffic to both the police and their local authority and each are doing their own surveys. It could be that the police have decided on the result of their survey that speed enforcement was necessary. One food for thought, it never ceases to amaze me that motorists, a lot that I know personally, regually drive at over 40mph though local villages and then at a later date are first to complain to their parish councils of speeding traffic in their own village. I only mention this as it is fresh in my mind from someone moaning in the pub last night. Amazing how many people have double standards when it comes to traffic violations.
Bob

What does my head in are motorists who do 45mph in a natioanl speed limit (60mph) and then carry on at same said 45mph in 30mph zones :o :confused: :(