Variable Speed Limit Cameras have recently been introduced on the M42 between Junctions 3A and 7 as part of the Highways Agency "Active Traffic Management" scheme. I know that the M25 has had these for a while so hopefully someone will know the answer to a question put to me by a friend (honest!).

The question is - when the gantry signs are indicating a lower speed than 70 mph, the cameras mounted behind them are set to detect vehicles travelling faster than the indicated speed. But is the same true when the signs are either off (blank) or where they are indicating NSL (usually at the end of a speed restricted section) ? i.e. will they 'do' you for exceeding 70 when there is no lower limit in force?

My guess is that they will (why waste a revenue-earning opportunity?) but maybe I'm just cynical

Anyone know for certain?

Rich

 

Not privy to the workings of them, but I'd always understood that they would reset to "normal" motorway speeds when no variable was set. (Whether that's 70 or 85 or whatever).

That is (reasonable) conjecture though, I don't work for the camera partnership.

 

On the M25 the cameras do not take pics when the variable is switched off. I have also done a 90 through the ones on the M42 with no fine.

 

I had a friend who used to work for the Transport Research Laboratory. His patch of monitoring was the M25.

He told me that the cameras on the M25 were set at 90 mph and in reality had no capacity to vary with the speed signs.

Now, that was some years ago and things may have changed.

 

According to the guy who is in charge of the safety camera partnership a gantry camera (gatso) is set to a certain detection speed and activated, it remains at that speed until manual intervention.

Any other sort of cameras I don't know but gatso's have 1 speed and cannot be updated remotely, ie when the limit is 50 instead of NSL the cameras will still be set to NSL plus a predertimed figure.

The trigger speed is set much like a combination lock, 3 revolving dials.

 

Well, you learn something new every day

 

Cheers Moff

My friend (ahem!) will feel much happier knowing that!

Rich

 

I beg to differ

I was "following" a Scooby that got flashed @ 85 mph on the M25 section going South between Heathrow & M3 @ NSL with flow control off.

Having said that I did travel through the M42 stuff at warp speed not long after it went live and never saw any photos.

BTW Moff when is your Indy 06 coming?

 

Hoping to confirm today, lease co has been very slow getting the order in

Next Indy's (only 2) are due in mid March, and I want delivery 8 April.

Fingers crossed!

 

A friend of mine was flashed at 85 on the m25 a week last sunday by one of the gantry cameras on the way down to gatwick. The variable speed limit signs were off.