Safe Speed Forums

I know there's a specific Trucking forum but I think this may be of general interest too. Also, those who have great knowledge of Road & Traffic matters, who are not truckers, may have some insight into this matter.

Had an interesting chat yesterday with a guy who teaches HGV drivers.

I knew there were sensors in the road which detect metalwork but he mentioned that some stretches have detectors buried in the road which can measure the actual weight of the vehicle passing over the Tarmac to detect whether it is a HGV or not.

Another surprise for me was they also use an infra red beam set high up, on posts or some such, and if the beam is interrupted that also indicates a HGV.

In either case the scamera does what scameras do best, except only to target this one group of course.

He went on to mention a case on a certain road where HGVs are meant to only do 40 mph maximum, (less than what cars are allowed to do). So for any truck just trying to keep up with the flow of traffic and not bog everyone down - snap!

He continued to mention a place where they'd set these devices up and overnight countless numbers of heavy goods drivers were done, some on several occasions resulting in a ban.

I don't know if anyone else has heard of this? (He seemed genuine enough).

If this is all true, I can think of situations where there could be false triggering etc, but perhaps someone could verify my story first?

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The views expressed in this post are personal opinions and do not necessarily represent the views of Safe Speed.
You will be branded a threat to society by going over a speed limit where it is safe to do so, and suffer the consequences of your actions in a way criminals do not, more so than someone who is a real threat to our society.

With revenue drying-up from car drivers, it was predictable that they would target van and truck drivers.
It sounds as if you didn't know that the legal speed limits for trucks are:
S/C roads: 40mph
D/C roads: 50mph
M/W roads: 60mph

For vans, not car-derived:
S/C: 50
D/C: 60
M/W: 70

Maybe it should also be mentioned that truck drivers do not have to amass points to be [effectively] disqualified, their LGV licence can be revoked.

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The world runs on oil, period. No other substance can compete when it comes to energy density, flexibility, ease of handling, ease of transportation. If oil didn’t exist we would have to invent it.”

56 years after it was decided it was needed, the Bedford Bypass is nearing completion. The last single carriageway length of it.We have the most photogenic mayor though, always being photographed doing nothing

You're right, I don't know what speeds they can do or indeed how to recognise what is a HGV if I'm honest. All I see is a big thing with lots of wheels, like many drivers I suspect. I'm just a regular driver who passed a regular test but at what point something gets so big or heavy it jumps into a different class, I have no idea.

I think you're right about 'let's get the rest of them'.

I've just had another thought: I can't imagine that they could weigh the vehicle very accurately on a road, the sensor wouldn't be under the entire vehicle for a start, but in my past work I have used something called a Load Cell. http://en.wikipedia.org/wiki/Load_cell

If this was buried under the Tarmac, I can see how it could be used to trigger the camera over a certain weight with one wheel bearing down.

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The views expressed in this post are personal opinions and do not necessarily represent the views of Safe Speed.
You will be branded a threat to society by going over a speed limit where it is safe to do so, and suffer the consequences of your actions in a way criminals do not, more so than someone who is a real threat to our society.

Why go to all that trouble (buried weight sensors) ?
They just have to re-set the truvelos' to 46 on s/c roads, etc.
With hand-held radar guns, they just target trucks and vans.

Goods under 7.5T are, and this means transits etc:
s/c: 50
d/c: 60
M/w: 70

Goods over 7.5T, as in my previous post.

Interesting to note that new drivers (car) can only drive up to 3300KG maximum weight on a car licence, and no trailers or caravans.

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The world runs on oil, period. No other substance can compete when it comes to energy density, flexibility, ease of handling, ease of transportation. If oil didn’t exist we would have to invent it.”

56 years after it was decided it was needed, the Bedford Bypass is nearing completion. The last single carriageway length of it.We have the most photogenic mayor though, always being photographed doing nothing

What he will have been referring to is the option in the Gatso radar control unit to set a separate speed threshold for "lorries".
I'm not quite sure how it detects the difference, it's either due to a larger radar return (bigger signal strength) or because if it knows the speed it can calculate the length.

Not perfectly accurate, and the photos have to be checked to see what legal class of vehicle it is, but that is what they can do and at least one county has been doing for a while so I hear.

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Andrew.

From the SCP and ABD pages -it would appear that at least Warwickshire have been doing this for some time - have heard tales of people living around the Redgate turn (A5/A444) talking of a lot of flashes with HGV in the night .

Another story on the A5 speaks of pole mounted speed sensors , but in light of the number of low bridges in the vicinity (and the length of time these have bee in situ) ,I would suggest that these are high vehicle sensors

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

Yep, especially if they are connected to a nearby sign which illuminates with words like "high vehicle turn back"

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Andrew.

Strangely enough - no sign of these ,which I think may have led to the speed idea .

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

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The views expressed in this post are personal opinions and do not necessarily represent the views of Safe Speed.
You will be branded a threat to society by going over a speed limit where it is safe to do so, and suffer the consequences of your actions in a way criminals do not, more so than someone who is a real threat to our society.

One thing I forgot. (but I have mentioned before)
You will quite often see inductive loops in the road. These are usually connected to a grey box on a pole which does basic data logging, and is used when they want to know the average speed for the "road".

So you find a site where there is "a speeding problem". If you put the speed camera down the road from one of there then it will still measure the average speed for the road pretty well. If you put the camera on top of it then it will measure the average speed as people slow down for the camera. A speed dip, if you were.

I guess the camera partnerships realised this so now they put the cameras on top of the data logging box loops so that they can say "Stats before camera: fast fast fast death destruction. Stats after camera: slow! camera is working! "

Looking at the stats for sites where I know the data logging boxes are away from the camera (like A351, Sandford, Dorset) can show that the camera is making no difference, very little difference, or in the case of Sandford the average speed is higher now than pre-camera. So to get people to slow down it should be removed?

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Andrew.

Interesting that ,Ziltro - from other sites (eg speedcam) I was led to believe that these loops were the sites of the early vans ( not used anymore because the LTI makes more cash).The early sites in Warks mention sites like this where evidence of loops can be seen .Know that up to about a year or two ago ,one site in Rugby had a van sited beside one of these grey boxes --but never saw any evidence of whether or not the method was LTI or loops .(Suspect strongly that LTI was used ,because WCC had installed a set of lights close to the site of the van ,and LTI could be set up to catch "customers" as they came into sight round a corner .

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

One of the few useful bits of information on the CSCP site....

http://www.cumbriasafetycameras.org/press/speedtable.jpg

It was available as a sticker at one time, which you could stick in the cab of your truck!
I was going to embed it, but apparently we are only allowed pictures up to 640 pixels wide!

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

they have been using various ways of detecting different categories of vehicle for years. i got caught out in 2002 on the A303 west of amesbury (is it chilmark?) doing 56MPH in a wagon and drag in a NSL zone in the middle of the night. the general rule is slow down to 40 for scameras. although it is not set in concrete, the northumberland police force seem very sensible. i did 6 months of running up and down the A1 over the border (lots of mixed SC/DC stretches) and i remember one (of many) occasion where i was between DC stretches on the limiter, slowed down for a scamera and foot down again. i hit a DC and the first vehicle to overtake was a police car. he had been behind me for miles. i didnt know this until he passed of course. all i could see was a white car in the mirror prior to him overtaking me but it goes to show that some police forces/officers do have common sense and decency. he had me bang to rights but he didnt bother me at all. this was during the day too! fair play.
on another occasion one of my colleagues was behind me heading south so its early hours (probably around 0330) when a small vehicle passed us (individually as there was a gap). i gave them a couple of winks to show the road was clear anyway and it turned out to be a small police van. he pulled in front of me and gently slowed to 40 so obviously that was a message to both me and my colleague behind. again, no further action. he sat there for a minute or 2 then went on his way.
the scameras are indiscriminate but at least the officers do show discretion depending on the cirumstances.

in fact i have even been let off by a mobile camera operator. 50 on a single lane carriageway. i heard one of the guys mention it back at base. he had been doing 50 too, saw it too late (it was a sneaky one on top of a hill in a layby) and we both expected NIPs but nothing turned up

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Richie

SSAFA supporter
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Yes, Northumberland have had them since at least 1998, before I retired. I couldn't believe it when I was first told!

That could well be because the definition of a "Dual Carriageway" has nothing to do in any shape, fashion or form with the amount of lanes in each direction.
What defines a Dual Carriageway is a central dividing barrier or reservation.

So you could have been on a two way road with a barrier (or grass ) dividing you from oncoming traffic and thats classed as a dual carriageway. YES you can do 50mph legally.

Or he could have been tucking into his donuts.

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The Box said "Windows XP or better" ... So I installed Ubuntu

What's this then?

Should I plant some grass up the middle?

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

Last I heard a dual carriageway is a road comprising two carriageways separated by land.


Three lane single carriageway with distracting white paint in the middle.

I forgot about other devices, any human operated device, well the human can say "that looks like a lorry, we can get them at a lower speed". Anything which does ANPR (like SPECS) could in theory tell what is classed as "lorry" if it could look at the database. Not sure if they do or not.

Oh and to make things more complicated the all motorways have the same speed limits, even single carriageway ones (I think there are a couple of very short ones left?). Street lamps don't mean anything on motorways either.

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Andrew.

it was single carriageway mate. 2 lanes going up the hill and 1 going down. the short dual carriageway had ended a couple of hundred yards before. anyone who knows the area will know where i mean. heading north past berwick. the last hill before the roundabout with morrisons on the right and the A1 north on the left (2nd exit). the scamera was in the layby on the right as you come up the hill

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Richie

SSAFA supporter
http://www.facebook.com/group.php?gid=126025031585

I had exactly the same happen to me on the A1 in the Londonderry area. Traffic Plod joined on to the A1, passed each truck in turn, dropped in front and gently slowed down to 50mph, then sped up to the next truck. Sensible enforcement. And a big thank you to that Plod who could just as easily pulled me and given me a ticket.

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Semper in excreta, nur quantitat variat.