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daggers1980
Hello all,

I was driving along the northbound M25 heading towards the M11 and when I came to a large stretch of the motorway that had no overhead VSL gantries, I saw some of the large electronic noticeboards at the roadside still appeared to have the HADECS radar gun attached to them. A couple were even painted yellow if I remember correctly. Do these carry out enforcement without the gantry cameras, or are they there for possible expansion of the VSL system in future?

I am not concerned about having been caught or anything - traffic wasn't moving that fast anyway! Just curious about the purpose of the radar where no gantry is present.

Thanks!
Jlc
HADECS3 has camera's at the roadside, see here.

There's also a slave camera that takes pictures to include the displayed limit.

HADECS2 was the overhead per lane gantry-based system.
daggers1980
So HADECS3 do not link up with the gantries, just the roadside signs?

I ask because I saw some of these nowhere near a gantry.
Jlc
HADECS3 is completely roadside equipment. (Other than knowing the displayed limit on the gantries)
trendi22
QUOTE (daggers1980 @ Tue, 22 Mar 2016 - 12:39) *
So HADECS3 do not link up with the gantries, just the roadside signs?

I ask because I saw some of these nowhere near a gantry.

They can do both.

The MS4 signs at the side of the road or the overhead gantries. The speed limit indicated on either type of sign can be enforced with HADECS3.

Thee MS4 sign has one speed limit sign that applies to the whole carriageway that it faces.

You will see HADECS3 cameras on gantries and on the MS4 signs.

They cover all lanes from one position at the side of the road.
Johnxxx
QUOTE (trendi22 @ Wed, 23 Mar 2016 - 07:45) *
... The MS4 sign has one speed limit sign that applies to the whole carriageway that it faces. You will see HADECS3 cameras on gantries and on the MS4 signs. They cover all lanes from one position at the side of the road.


I have been puzzled by this for some time. The "Old" TSRGD required a Start and End (NSL) Speed Limit sign to be placed on both sides of the carriageway and for repeaters to be placed at certain distances and on alternate sides of the carriageway.

IMHO the new cantilevered variable message signs (which are defined to be alongside the carriageway, even if the are partly above the carriageway) do not fulfil these requirements. I've had a quick look through the new 2016 TSRGD but can't find the equivalent wording.

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