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M5 Variable Speed Camera's - when do they flash?

M5 Variable Speed Camera's - when do they flash?

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Discussion

EasyMalt

Original Poster:

2 posts

23 months

Monday 4th January 2016
quotequote all
Earlier this evening I was N-bound on the M5, no variable speed limit was displayed and I was happily doing an indicated 70 being wary of the speed cameras. On the approach to one of the gantries I was overtaken, and then as I went over the lines the camera flashed. The overtaking vehicle was already passed the lines, so my question is when does the camera flash? I always assumed it flashed twice while the speeding vehicle is on the lines, but this seems to suggest it doesn't actually use the lines and only flashes after the vehicle is past them to capture the number plate?
Or can I expect a NIP in the post in a few days...?

(edit: I accidentally an apostrophe)

RemaL

24,165 posts

158 months

Monday 4th January 2016
quotequote all
If you are doing 70 indicated and there was no reduction on the speed limit don't worry

I've gone past them over 75 and had no issues

hornetrider

63,161 posts

129 months

Monday 4th January 2016
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They are active when no restriction is in place though. I found this out the hard way - was pinged at 87.

BristolRich

543 posts

57 months

Monday 4th January 2016
quotequote all
In addition to previous posts...

There are two systems in operation at the moment on the M5 at Almondsbury...GATSO which are mounted on gantries above each of the lanes, and HADECS which are mounted on the left hand side of some of the gantries (as you approach them).

The GATSOs are as other speed cameras of this type rely on either radar, induction loop or combination of both. Typically these flash once as a "test", twice as you pass through the camera above the set limit. I have seen the cameras "erroniously flash" with single flashes - myself included.

The HADECS system is different. Sensors are mounted on top of a tee shaped post on the motorway verge some distance ahead of the gantry mounted camera. As you pass the sensor this will detect over threashold and "snap" you as you go past the gantry mounted camera. If for example you exceed the posted limits between the gantries, it would take a pic. No idea how many times these flash, however the location of the flash would be an idicator as the flash units are mounted over your left shoulder as you pass.



TDIfurby

1,997 posts

99 months

Monday 4th January 2016
quotequote all
Camera probably got the other car, and you maybe thought by the time you had seen the flash and clocked the other car, it was over the lines, when in fact it was snapped whilst over the lines. smile
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theboss

3,507 posts

143 months

Monday 4th January 2016
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They will go off when set to NSL / no speed limit shown... though there is some tolerance. In the absence of any marked restrictions I wouldn't personally do more than an indicated 80 under those gantries, which is 76-77 in my car. I suspect only a few gantries are equipped with cameras.

giltranator

317 posts

112 months

Monday 4th January 2016
quotequote all
I am under the impression that they haven't been working over the past 4-5 months until a few weeks ago when I started seeing the flashes a lot more frequently. Seems a bit strange but I travel on that stretch of M5 5 days a week and months passed without a flash and then over the past two weeks i've seen a flash every 2-3 days, mostly from the northbound ones just before the A38 Aztec West junction where the limit normally drops to 40 in the mornings.

EasyMalt

Original Poster:

2 posts

23 months

Monday 4th January 2016
quotequote all
BristolRich said:
In addition to previous posts...

There are two systems in operation at the moment on the M5 at Almondsbury...GATSO which are mounted on gantries above each of the lanes, and HADECS which are mounted on the left hand side of some of the gantries (as you approach them).

The GATSOs are as other speed cameras of this type rely on either radar, induction loop or combination of both. Typically these flash once as a "test", twice as you pass through the camera above the set limit. I have seen the cameras "erroniously flash" with single flashes - myself included.

The HADECS system is different. Sensors are mounted on top of a tee shaped post on the motorway verge some distance ahead of the gantry mounted camera. As you pass the sensor this will detect over threashold and "snap" you as you go past the gantry mounted camera. If for example you exceed the posted limits between the gantries, it would take a pic. No idea how many times these flash, however the location of the flash would be an idicator as the flash units are mounted over your left shoulder as you pass.
Interesting, thanks! Sounds like it could have been a hadecs camera, or perhaps just a "warning" flash to the other driver.

As others have said, definitely seems like the cameras are being used more now, I'd never seen a flash along the M5 before, but this was the second time in the last week I've seen it - rumours also flying that A&S constabulary are no longer observing the 10%+2 guidance, perhaps a FOI request could clear up that particular piece of hearsay. Anyway, I'll keep an eye on the mail just in case (because I'm a paranoid sort) but in the unlikely case something does come I'll definitely be contesting.

hornetrider

63,161 posts

129 months

Monday 4th January 2016
quotequote all
giltranator said:
I am under the impression that they haven't been working over the past 4-5 months until a few weeks ago when I started seeing the flashes a lot more frequently. Seems a bit strange but I travel on that stretch of M5 5 days a week and months passed without a flash and then over the past two weeks i've seen a flash every 2-3 days, mostly from the northbound ones just before the A38 Aztec West junction where the limit normally drops to 40 in the mornings.
Funnily enough I saw one flash today on the northbound side approaching Aztec as I was heading south. Traffic was light and the car was certainly motoring.

BristolRich

543 posts

57 months

Tuesday 5th January 2016
quotequote all
EasyMalt said:
BristolRich said:
In addition to previous posts...

There are two systems in operation at the moment on the M5 at Almondsbury...GATSO which are mounted on gantries above each of the lanes, and HADECS which are mounted on the left hand side of some of the gantries (as you approach them).

The GATSOs are as other speed cameras of this type rely on either radar, induction loop or combination of both. Typically these flash once as a "test", twice as you pass through the camera above the set limit. I have seen the cameras "erroniously flash" with single flashes - myself included.

The HADECS system is different. Sensors are mounted on top of a tee shaped post on the motorway verge some distance ahead of the gantry mounted camera. As you pass the sensor this will detect over threashold and "snap" you as you go past the gantry mounted camera. If for example you exceed the posted limits between the gantries, it would take a pic. No idea how many times these flash, however the location of the flash would be an idicator as the flash units are mounted over your left shoulder as you pass.
Interesting, thanks! Sounds like it could have been a hadecs camera, or perhaps just a "warning" flash to the other driver.

As others have said, definitely seems like the cameras are being used more now, I'd never seen a flash along the M5 before, but this was the second time in the last week I've seen it - rumours also flying that A&S constabulary are no longer observing the 10%+2 guidance, perhaps a FOI request could clear up that particular piece of hearsay. Anyway, I'll keep an eye on the mail just in case (because I'm a paranoid sort) but in the unlikely case something does come I'll definitely be contesting.
Images of the HADECS set up as on the M4/M5 interchange can be seen here...

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

IIRC there is one set each way M5 - NB/SB, M4 - EB/WB. All sets are mounted to gantries with overhead GATSO style cameras.

AngryApples

5,442 posts

189 months

Wednesday 20th January 2016
quotequote all
Most annoying thing I've noticed is the amount of morons that seem to believe the 60 MPH is permanently in force

I regularly travel through the camera zones outside of standard rush hour (0530 - 0630 and 1530 to 1600) yet with no restriction signs showing there are still countless idiots travelling in the middle/outside lanes doing 55-60

I may just need an anger management course but when I'm trying to get home and I'm surrounded by these people I find it a massive urine steamer!

I have actively avoided undertaking throughout my driving years, but this has lead me to even resort to that

RemaL

24,165 posts

158 months

Wednesday 20th January 2016
quotequote all
pretty much the same is happening around Bristol as a few people think every road is a 20 limit and drive at 19MPH in a 30 FFS

GlenMH

4,763 posts

167 months

Sunday 24th January 2016
quotequote all
AngryApples said:
I have actively avoided undertaking throughout my driving years, but this has lead me to even resort to that
Yup - the number of times I have gone through that area on an open and empty hard shoulder lane at the posted limit and overtaken loads of people to my right....

Thanks for the info about HADECS - I had spotted the camera system and wondered what it was.

dirtyweesyds

1 posts

14 months

Wednesday 5th October 2016
quotequote all
I have just been flashed by an overhead gantry on the M5 s/b around the m48 junction but was traveling around the 90 Mark but I think it only flashed once but can't be 100% sure on that, do I need to expect a brown envelope in the post? Thanks

hornetrider

63,161 posts

129 months

Wednesday 5th October 2016
quotequote all
dirtyweesyds said:
I have just been flashed by an overhead gantry on the M5 s/b around the m48 junction but was traveling around the 90 Mark but I think it only flashed once but can't be 100% sure on that, do I need to expect a brown envelope in the post? Thanks
Sadly, yes

MrC986

1,850 posts

115 months

Tuesday 18th October 2016
quotequote all
I know the cameras work past Cribbs Causeway when the variable limits not displaying....83 mph & an NIP or driver awareness course was offered - fortunately no more weekly commuting to the South West will prevent it happening on that section of motorway!

Raebs

1 posts

1 month

Sunday 19th November
quotequote all
I was driving my Hgv lorry last week going down the M5 southbound early in the morning no speed was being displayed on the gantry above , I was doing 56mph and the camera flashed me, and later on coming back up on the M5 northbound same section gantry above was displaying 60mph and I passed at 56mph and it never flashed?? So iam wondering how it flashed in the first place , if I get a ticket for speeding surely I can appeal this as no speed was being displayed ?

Stuart J

931 posts

181 months

Monday 20th November
quotequote all
Raebs said:
I was driving my Hgv lorry last week going down the M5 southbound early in the morning no speed was being displayed on the gantry above , I was doing 56mph and the camera flashed me, and later on coming back up on the M5 northbound same section gantry above was displaying 60mph and I passed at 56mph and it never flashed?? So iam wondering how it flashed in the first place , if I get a ticket for speeding surely I can appeal this as no speed was being displayed ?
Its your word against them & you will have no proof if a conventional camera


I don't know the road but if its Hadex then they have another camera before the Gantry that records the Gantry to show whats displayed & you have a small period of grace after the limit lowers, but I don't think Hadex flash,

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

On the site it says they are here in Somerset https://www.speedcamerasuk.com/database/SWS/sws079...


Edited by Stuart J on Monday 20th November 15:03

supercommuter

1,228 posts

26 months

Wednesday 22nd November
quotequote all
Have regularly gone through the GATSO ones at 80mph when not concentrating and not been flashed, Always slow down for the side mounted yellow ones! I actually didn't think the GATSO ones worked anymore.

markymarkthree

226 posts

95 months

Thursday 23rd November
quotequote all
Stuart J said:
Raebs said:
I was driving my Hgv lorry last week going down the M5 southbound early in the morning no speed was being displayed on the gantry above , I was doing 56mph and the camera flashed me, and later on coming back up on the M5 northbound same section gantry above was displaying 60mph and I passed at 56mph and it never flashed?? So iam wondering how it flashed in the first place , if I get a ticket for speeding surely I can appeal this as no speed was being displayed ?
Its your word against them & you will have no proof if a conventional camera


I don't know the road but if its Hadex then they have another camera before the Gantry that records the Gantry to show whats displayed & you have a small period of grace after the limit lowers, but I don't think Hadex flash,

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

On the site it says they are here in Somerset https://www.speedcamerasuk.com/database/SWS/sws079...


Edited by Stuart J on Monday 20th November 15:03
He will have proof of the speed he was doing if driving an HGV.



Edited by markymarkthree on Thursday 23 November 13:45