Hi all. Travelling down the M1 yesterday evening, there was some road works being set up in lane 1. The speed limit was therefore incriminatory decreased to 40 while passing. No problems there. As I pass and lane one became free again I naturally merged back and noticed none of the overhead signs were illuminated with any information or speed limit, so I naturally sped up. It wasn’t until I was about to reach my exit around a mile down the road where I noticed the overhead sign displaying the national speed limit sign. I’m now very worried that since I passed a camera, the argument will be that although the over head signs were not illuminated to say 40/50/60, I’ve been copped because I sped up before being intructed to. Has anyone else experience something similar??

I’ve been told that there’s a set of cameras trained on the overhead signs before speed cameras which take an image of the variable speed limits, anyone know anything about these?

Thanks in advance

Strictly the limit applies until you see the national sped limit sign.

However the camera's are linked to the gantries and only enforce when the gantry is validly displaying a limit, no limit displayed and the camera should be off.

As it's not a live case this thread will probably move to the flamepit forum unless or until you get something that makes it a live case.

Not quite right.
When the gantry signs are either unlit or have a faulty sign displayed, the cameras enforce NSL(70).

Yes, lots - HADECS3.

What part of the M1 out of curiosity?

Between J26 & J28 many of the gantries don't have any cameras on them, the 'rumour' at the time was that they were a victim of the spending cuts put in place by the incoming coalition on 2010, IIRC this section went smart in 2011. When I occasionally use this stretch it is obvious that regular users know which gantries do & don't have cameras judging by the speeds they pass them at.

A quick drive north from J26 on GSV doesn't reveal any cameras

https://goo.gl/maps/D6TXjvbKsMjJgK49A

With just 2 gantries having them between 27 & 28.

https://goo.gl/maps/UQVsmzpXonE6JwuZ9

This was just before junction 40. (South Bound)

J40 has HADECS3 - here. (Cameras on the far left)

It does- which is my cause for concern. However, the gantry signs were not illuminated, and neither was the large single sign before it. Nevertheless, there was no indication it was NSL either, unless we assume that no information = NSL applies like some have suggested. Hopefully it’s the latter!

I have a TomTom with traffic and speed cameras.
Someone has kindly entered all the camera locations on the M1 gantries onto the database.

The auxiliary camera would take a picture of blank signs if triggered... (The idea is the displayed limit is contemporaneously snapped - they are effectively showing NSL...)

Apart from these?

Hadecs3

‘Between J26 & J28 many of the gantries don't have any cameras on them, the 'rumour' at the time was that they were a victim of the spending cuts put in place by the incoming coalition on 2010.’

Doubt that very much. Unless my TomTom is wrong. Or this map is too.

They’re every few gantries just like on other motorways such as the M25.

Dunno about M1 but other motorways?

Older satnav maps such as mine (2011) may well say there are cameras.
May well be cross lines on the carriageways which further imply there are cameras.
But many gantry cameras have or are being replaced with Hadecs and not necessarily in the same place.
Speed while relying on notional camera positions on M6 north for instance, J6 to J10, you would be braking to the speed limit every other gantry.
And totally miss the only camera in that stretch, a Hadec between J7 and J8

Either TomTom or someone else is very diligent as I don’t speed but I do make a note of camera locations vs device as I see them and the device (with updates) is always right.

Its been a few years since I had a TomTom but the one I had included a facility to report cameras. Quick press on the screen and another press for camera type.
It was pretty good at reporting mobile speed cameras that had been noted by users.

I had a Tom Tom with that facility The only downside was that I was forever pressing buttons telling Tom Tom that the cameras being displayed were no longer there !

I never bothered with that, leave people slowing down (I think it removed mobile ones automatically when they weren't reported after a while)