Speed cameras and different limits

[bmw114]

Can a fixed speed camera tell the difference between cars and hgvs.
On parts or the A5 the speed limit is 50 mph so its 40 mph for trucks surely to tell the difference they would have to put weight sensors in the road, but you could be driving a Motorhome.
Anybody know the facts.

[bluepolarbear]

bmw114 said:

Can a fixed speed camera tell the difference between cars and hgvs. On parts or the A5 the speed limit is 50 mph so its 40 mph for trucks surely to tell the difference they would have to put weight sensors in the road, but you could be driving a Motorhome. Anybody know the facts.

yes they can and have different limits set.

[smeggy]

bmw114 said:

Can a fixed speed camera tell the difference between cars and hgvs. On parts or the A5 the speed limit is 50 mph so its 40 mph for trucks surely to tell the difference they would have to put weight sensors in the road, but you could be driving a Motorhome. Anybody know the facts.

Apparently gatsos (radar) can:

speed trap bible said:

The unit can also differentiate between large vehicles and cars by the amount of radar return, so a lower activation threshold can be set for large goods vehicles and coaches. This explains why sometimes you see a truck that is doing 70mph on a dual carriageway trip a camera when a car at the same speed does not - it has registered that the truck was going too fast (trucks are limited in top speed).

www.speed-trap.co.uk/Accused_Home/Gadgets/Gadgets_Home.htm

SPECS (averaging by digital cameras) can perfom a database lookup to determine what kind of vehicle passed though the trap and apply the limit accordingly.