Radar for dashCamera

[Nigel]

but i cant recall seeing the cancel sign + a new speed sign, and so both me and a self driving car would have a hard time knowing what the sped limit is.

Not a problem, they are canceled by default after a set distance, and if the road works or whatever is longer than the set distance then there must be a repeat speed limit sign (normally a small version of the main speed limit sign) every time the set distance expires, which is why you sometimes see a repeat speed limit sign only a few meters before the cancel sign.

 

[kamkar]

I dont think it is like that here, just 1 sign for roadworks / lowered speed limit, and just 1 to cancel all that after the location.
Okay there are also often a graduate speed lowering, not least on motorways where going from 130 to say 80 is way more than the average Dane can handle, and which are also often seen where motorways transform to a highway, cuz right after that 90 speed sign, you will often find police measuring speed.
So motorways you see signs way before the road works.

 

[MaXyM]

yeah.. but there is another case when all extra signs are cancelled. It's roadcross. It means set default signs after each one.