Bizarre Speed Restrictions on the M25

[gbjeppm]

Has anybody else noticed this before.

I was driving anti-clockwise around the M25 at about 6:30 pm the other night, and was just approaching the M3 at Junction 12.

The overhead gantrys were showing speed restrictions of 40, 40 and 60 from left to right.

I did not think that the system was setup to have differing speeds in different lanes. I am sure it was a mistake, but if you happen to get a ticket for doing 60, then it will be an interesting argument.

 

[James Rothwell]

This probably isn't true but sure someone told me that if they are flashing they are only advisory and if the circles either side of the limit are constantly lit then it is a reduced limit?

 

[MBManInKen]

Aren't there 5 boards there? Two on the lanes leading to the sliproad to the M3, indicating the speed restrictions for the M3 and three for the lanes continuing on the M25?

You can get different speed restrictions at these places for the lanes leading to the other motorway.

 

[BTB 500]

AFAIK in the variable speed limit section the speed shown on the gantry is always mandatory. Never seen different limits per lane, but this is used on the continent (certainly in Germany) so maybe being trialled?

 

[JumboBeef]

I have seen different speed limits on different lanes before, usually ahead of lane closures (the lanes closed ahead have the lower speed limits to encourge you to get into the faster, open lane).

 

[gbjeppm]

Aren't there 5 boards there? Two on the lanes leading to the sliproad to the M3, indicating the speed restrictions for the M3 and three for the lanes continuing on the M25?

You can get different speed restrictions at these places for the lanes leading to the other motorway.

Yes there are, but these were the main 3 boards, with the 60 being on the outside lane. The next set the other side of the junction incidentally said 40 40 40.

 

[Dryce]

AFAIK in the variable speed limit section the speed shown on the gantry is always mandatory. Never seen different limits per lane, but this is used on the continent (certainly in Germany) so maybe being trialled?

There must be a difference between the red circle enclosed variable limits on the gantries and the traditional ones with the orange flashing lights.

Otherwise they wouldn't need to different types of representation.

The overhead lane limits with the orange flashing lights used to be advisory but ISTR there was a change to that around 10+ years ago. They can now be enforced.

I would guess there's a legal difference in terms of enforcement. With the red circle they presumably have the same authority as a standalone traditional sign.

That means you can use cameras and issue a fixed penalty perhaps? Whereas the traditional type can't be camera enforced.

 

[stevesey]

Has anybody else noticed this before.

I was driving anti-clockwise around the M25 at about 6:30 pm the other night, and was just approaching the M3 at Junction 12.

The overhead gantrys were showing speed restrictions of 40, 40 and 60 from left to right.

I did not think that the system was setup to have differing speeds in different lanes. I am sure it was a mistake, but if you happen to get a ticket for doing 60, then it will be an interesting argument.

Could just be a changeover glitch as the signs changed from 40 to 60 - may have only been present for the few seconds you were in range.

Next time I'm in the office all ask one of our project managers as we managed a lot of the software implementation those.

 

[Marque]

The overhead gantrys were showing speed restrictions of 40, 40 and 60 from left to right.

I've seen this before. It is sometimes used when there is (or was) congestion on the exit slip road that causes traffic to slow in the left-hand lane (or lanes) but the rest of the motorway is clear. I believe 40 is the lowest variable speed limit that is permitted.

 

[Diesel Benz]

Next time I'm in the office all ask one of our project managers as we managed a lot of the software implementation those.

And they all show 100 when your car is approaching?

 

[BTB 500]

There must be a difference between the red circle enclosed variable limits on the gantries and the traditional ones with the orange flashing lights.

Otherwise they wouldn't need to different types of representation.

The overhead lane limits with the orange flashing lights used to be advisory but ISTR there was a change to that around 10+ years ago. They can now be enforced.

I would guess there's a legal difference in terms of enforcement. With the red circle they presumably have the same authority as a standalone traditional sign.

That means you can use cameras and issue a fixed penalty perhaps? Whereas the traditional type can't be camera enforced.

The variable speed limit gantries are legally the same as a fixed sign.

AFAIK the old orange LED ones are still advisory. They're incredibly unreliable - we use the motorways a lot early in the morning at weekends, and it's rare to do a trip without running into a random 50 mph somewhere on a deserted motorway.