can a speed camera differentiate between different classes of vehicles?

[danchip]

Is a speed camera in a van set up so that it can catch different types of vehicles doing different speeds?

[alexanderd]

surely they just detect speeds, doesnt matter what vehicle it is

[Squitty]

Roadside speed cameras dont flash caravans speeding past their limit of 60mph on dual carriageways where the limit for everybody else is 70.

[hc4361]

It does matter, Alex. Some classes of vehicle have lower speed limits than cars. For example, HGV cannot exceed 58mph on a motorway.

[sallybb]

According to an ex speed cop we know, they can take the speed of more than vehicle at a time. If thats what you mean

[alexanderd]

I agree Squitty but the ones in vans register the speed of every vehicle passing. They dont flash

[Squitty]

thats different alex because the police behind the camera in a van chooses to report a caravan in the same circumstance. A roadside speed camera has no choice.

[danchip]

what i meant is that say the road is a single carriageway road and the speed limit for cars is 60mph, a bus is only allowed to do 50mph on this type of road as are certain goods vehicles and HGV's are restricted to 40mph!

So are these camera's sophisticated enough to catch a car doing over the limit at 60, a bus exceeding 50 and a HGV exceeding 40 if the 3 vehicles passed them one after the other?

[alexanderd]

I agree with all the comments but,as I said, the cameras in vans record speeds regardless of the vehicle so if an hgv was doing 58 in a 60 limit but he was restricted to 50 then he would be caught surely

[Squitty]

Danchip - In my experience the answer is no. I gave you the caravan example because I was so confident I was right that I tried it to prove a point.

[danchip]

i was always under the impression that they were set to a specific speed and vehicles over that speed set it off as such!

Do the cameras take photos of every vehicle and then someone checks the speed?

[KJN]

I think the last paragraph answers you question;-
Gatso Meter Speed Cameras

By far the most popular choice for police forces and local authorities across the UK. The Gatsometer BV company which originates from the Netherlands, was founded in 1959 by Maurice Gastonides, a famous rally driver and winner of the Monte Carlo Rally in 1953.

The Gatso speed camera uses radar technology (radar type 24), the equipment can be used in a stationary position, in a car, in a trailer on a tripod or from a moving vehicle. Fixed installation post (F.I.P) Gatso speed cameras are rear facing as they use a 'flash' to capture the image required for prosecution, which would distract a driver if forward facing.

The images are stored on a standard 35mm 'wet film', which needs to be changed and processed. With each film reel only having the ability to take 400 pictures before needing to be changed, cameras in busy places or where speeding offences occur more often can only last a few hours before needing to change the film.

Some Gatso's can also tell the difference between a car and HGV, so if for instance the limit was 60 mph for cars and for HGV's it was 40 mph, if HGV's pass the threshold of approx 45-50mph the camera would be triggered.

[New Judge]

"...HGV cannot exceed 58mph on a motorway."

Not quite right, hc:

http://www.theanswerb.../Question1058912.html

[chas2008]

yep, picks up the number plate, how do you think they get the summons, i know people who have been done driving long wheel base sprinters as the max speed on a dula carraigway is different to a std van.

[chas2008]

yep, they are not supposed to exceed 58 mph but they do, foreign registered vehicles being the biggest culprits.

[New Judge]

No, not correct chas.

The speed limit for large HGVs on motorways in the UK is 60mph. Not 58mph, not 56mph. You will see in the earlier question to which I referred, a link to Schedule 6 of the Road Traffic Act 1984 which sets out the various speed limits.

The 56mph figure comes in because that is what speed limiters on HGVs have to be set to in order to comply with an EU directive. There seems to be quite a high degree of confusion about this, even among HGV drivers. It is an unfortunate side effect of EU regulations being imposed in the UK and arises particularly because the EU insists on imposing regulations such as this in metric units (56mph is 90kph) with no latitude for conversion to imperial measures..

[trailertam]

The fixed camera sites that flash do so when the speed limit for cars at that point is being exceeded, and is triggered automaticaly by radar or similar device. The method used from the mobile vans parked next to the carriageway is to record on video tape, or similar, vehicles approaching the camera and what speed they are travelling at being shown on the recording. This way different classes of vehicles will be detected breaking their individual speed limits. These recordings are examined at a later time by a person who decides which vehicles are breaking their speed limit.

[rov1100]

I have often though about this while driving. If the speed limit on a dual carriageway is 70 for cars how does it know the vehicle is a car if a lorry is doing say 65?

[Boiler-man]

As far as I know these cameras film all Trafic and are checked by the camera operative who then determines whether the vehicle is speeding or not. I was done on the Aberdeen - Dundee Road for driving on dual carriageway with National Speed Limit at 69MPH in my Renault van. National Speed Limit for a van is 60 on dual carriageway and 50 on a single carriageway whereas it us 70 & 60 for cars.

[Hopkirk]

I'm afraid you are out of date Danchip.

The speed limit for HGVs on single carriageways has been raised to 50mph in England and Wales. It remains at 40mph in Scotland.

When it was 40mph, I know of someone who was caught by a fixed camera in an place where a car would have been legal. I don't know if the camera recognised the vehicle size, or if someone had to look through the images.