Variable speed m25

[Baaaartz]

Just drove past junction 25 on the m25, 3 lanes were set at 40mph and the slip road at 20mph, I seen people in the slip road going atleast 35mphz keeping up with me pretty much in the 40mph lanes.

Do these cameras only enforce one speed limit or can they enforce 2 speed limits at the same time?

Example sliproad 20mph, other 3 lanes at 40mph.

[NortonES2]

Believe each lane has its own camera, so yes they could be set for different speeds.

[Baaaartz]

So one camera on the side of the gantry technically can watch 4 lanes at 4 different speeds is what your saying?

I haven't seen the camera flash any of the people going 35mph or so in that 20mph zone?

[Dave Hedgehog]

Baaaartz said:

So one camera on the side of the gantry technically can watch 4 lanes at 4 different speeds is what your saying?

I haven't seen the camera flash any of the people going 35mph or so in that 20mph zone?

very easy to do in software

[NMNeil]

Baaaartz said:

So one camera on the side of the gantry technically can watch 4 lanes at 4 different speeds is what your saying?

I haven't seen the camera flash any of the people going 35mph or so in that 20mph zone?

"The innovation that allows Hadecs to be used on a smart motorway is its ability to adjust its detection speed according to the variable speed limit that's posted. It does this by receiving information from sensors further along the carriageway, so when you see a lower limit posted on a smart motorway, the Hades cameras ahead can catch you for breaking it.
As well as speeding, Hadecs cameras can be set up to monitor up to five lanes, and they can detect vehicles that are using closed motorway lanes. As they are radar-based, they are able to work in all weather conditions, too."
https://www.autoexpress.co.uk/car-news/106377/uk-s...

[mygoldfishbowl]

"REDFLEXhadecs3 uses non-intrusive dual radar for the detection of speed offences in all weather conditions, with lane identification, vehicle position and positive vehicle identification. In this application, the system is to be used for monitoring up to five lanes of traffic, consisting of a hard shoulder, which may or may not be a running lane, and four running lanes."

From here. https://www.speedcamerasuk.com/hadecs-3.htm

[KingNothing]

Is it even legal to display two different speed limits on the same road? I’ve never seen a different speed limit across a smart motorway dependant on lanes, only closing or closed lanes signs.

[BertBert]

KingNothing said:

Is it even legal to display two different speed limits on the same road? I’ve never seen a different speed limit across a smart motorway dependant on lanes, only closing or closed lanes signs.

We've been through this in quite some length a while back and eventually concluded that different limits in different lanes couldn't work, but when a side lane becomes a separate lane through the markings it can have a different limit.