M1 Smart Motorway Speed Cameras

tsears

Hi there,

I'm a little worried, I was just on the M1 coming up to junction 13 for Bedford traveling North bound and the speed signs above were set to 50mph which I was doing. On passing the cameras I noticed it flash and I was definitely doing 50mph as had my cruise control set. I noticed further along the motorway (a mile or so) the speed was set to 40mph. If when I passed the camera that flashed and the speed changed from 50 to 40 as I went through, would the camera set off right away? Or would there be a delay as otherwise I would have to slam on my breaks, as I wouldn't have even seen it change if it did.

Also, it may have been the van behind me that set it off as didn't notice the flash right away, if it was and I was in the photo, would it recognise it was the other vehicle speeding?

Just a little worried, so hoping someone can clarify how they work.

Many thanks,
Tom

DoaM

I believe the targeting system in the cameras gives focus to the vehicle that has been detected, not every vehicle that happens to be in-frame.

jimbo6977

The official handbook states a minimum of 1 minute is to be allowed between a change in the posted limit and any enforcement by camera.

The unknowns:
Is the 1 minute gap adhered to? Is it possible to show that it is adhered to? Are the contents of a "handbook" somehow enforceable at law?

jk0

Beware something similar on the M4 westbound between J10 & 11:


There is a long section of 50mph 'roadworks' monitored by average speed cameras. When you see the sign cancelling this, it is human nature to accelerate. However, there is a final camera on a yellow pole right by the sign.

Nasqueron

jk0 wrote: »

Beware something similar on the M4 westbound between J10 & 11:


There is a long section of 50mph 'roadworks' monitored by average speed cameras. When you see the sign cancelling this, it is human nature to accelerate. However, there is a final camera on a yellow pole right by the sign.

So long as you don't accelerate until you pass the NSL sign, what is the issue?


I am not going to do the maths but I would suspect also given that the limit was 50 and cars usually overstate the speed by about 10%, you're probably doing 45-46mph anyway, so a short acceleration over the last 100m or whatever might not be enough to increase your average to over 50, particularly over a long stretch.

family4tunes

If you were doing 50 mph like you said there is nothing to worry about. If the camera flashed its likely the van that set it off. The smart cameras are on 24/7 and set at 70 mph unless the overhead signs say different.

There can be times when the next sign will be for a slower speed so you must look a head to make sure you are at the correct speed for each camera when passing underneath. Sometimes this might have a yo-yo effect ie: 60, 50, 40,50,40,30, 40, 40, 50 all clear etc. You must obey each sign each time even though its frustrating.

The signs should not drop or raise you by more than10 mph each time to enable you to react. Just be careful as these smart motorways have trip plates underneath the tarmac which are used to judge the flow of traffic and automatically set the signs for speeds. This is why sometimes they will be on for no reason you can see (RTC, Roadworks, Object in road etc) its because some motorist has been following a car to close and tripped the cameras into thinking there is a queue of traffic, thus its starts slowing following traffic down.

It sounds to me like you have nothing to worry about so don't panic. Just watch the mail box because if you have been nabbed, you will be notified within 2 weeks for sure. just a note, the white line underneath the cameras will show which car was at fault because of the distance travelled between flashes. If you were doing 50 mph like you say, it will show that you were not the offender the van was.

Just a note about average speed cameras. Don't take every camera to be live, in a run of cameras say for example 6 only 2 of them might be recording the average. This could be camera 2 and 5, or cameras 1 to 4 or even 3 to 6. Don't take for granted each one will record an average as they do not all have to be in use, just a minimum of 2 to do the maths.

Don't be hoodwinked into thinking that you passed say 2 cameras above the limit so by travelling slower for the next 4 will put things right as cameras 1-3 might be live so that judgement will be out the window and you will get a ticket.

Hope this info helped.

Mercdriver

family4tunes wrote: »

If you were doing 50 mph like you said there is nothing to worry about. If the camera flashed its likely the van that set it off. The smart cameras are on 24/7 and set at 70 mph unless the overhead signs say different.

There can be times when the next sign will be for a slower speed so you must look a head to make sure you are at the correct speed for each camera when passing underneath. Sometimes this might have a yo-yo effect ie: 60, 50, 40,50,40,30, 40, 40, 50 all clear etc. You must obey each sign each time even though its frustrating.

The signs should not drop or raise you by more than10 mph each time to enable you to react. Just be careful as these smart motorways have trip plates underneath the tarmac which are used to judge the flow of traffic and automatically set the signs for speeds. This is why sometimes they will be on for no reason you can see (RTC, Roadworks, Object in road etc) its because some motorist has been following a car to close and tripped the cameras into thinking there is a queue of traffic, thus its starts slowing following traffic down.

It sounds to me like you have nothing to worry about so don't panic. Just watch the mail box because if you have been nabbed, you will be notified within 2 weeks for sure. just a note, the white line underneath the cameras will show which car was at fault because of the distance travelled between flashes. If you were doing 50 mph like you say, it will show that you were not the offender the van was.

Just a note about average speed cameras. Don't take every camera to be live, in a run of cameras say for example 6 only 2 of them might be recording the average. This could be camera 2 and 5, or cameras 1 to 4 or even 3 to 6. Don't take for granted each one will record an average as they do not all have to be in use, just a minimum of 2 to do the maths.

Don't be hoodwinked into thinking that you passed say 2 cameras above the limit so by travelling slower for the next 4 will put things right as cameras 1-3 might be live so that judgement will be out the window and you will get a ticket.

Hope this info helped.

Some useful info there, but some not quite 100% correct.

I agree that you should assume that where there are cameras you should assume they are enforcing NSL if not lit with any other limit. This should be in accordance with normal procedure so enforcement starting at 10% +2.

As far as Average Speed Cameras are concerned, they don't take an average speed at all in the speeds at which the cameras are passed. They measure the amount of time it takes a car to travel between two given points - you won't know which two given points at all, they won't necessarily be in any kind of sequence...It's the basic mathematic definition of average speed.

Car_54

family4tunes wrote: »

It sounds to me like you have nothing to worry about so don't panic. Just watch the mail box because if you have been nabbed, you will be notified within 2 weeks for sure.

Only “for sure” if the OP is the registered keeper.

Nearly_Old

family4tunes wrote: »

Just be careful as these smart motorways have trip plates underneath the tarmac which are used to judge the flow of traffic and automatically set the signs for speeds. This is why sometimes they will be on for no reason you can see (RTC, Roadworks, Object in road etc) its because some motorist has been following a car to close and tripped the cameras into thinking there is a queue of traffic, thus its starts slowing following traffic down.


Just a note about average speed cameras. Don't take every camera to be live, in a run of cameras say for example 6 only 2 of them might be recording the average. This could be camera 2 and 5, or cameras 1 to 4 or even 3 to 6. Don't take for granted each one will record an average as they do not all have to be in use, just a minimum of 2 to do the maths.

Hope this info helped.

A couple of corrections:
There are no "trip plates". MIDAS (Motorway Incident And Automatic Signalling) detector loops are located every 500m in every trafficked lane. Its nothing to do with two cars being close and tripping the cameras as it doesn't involve the cameras. There has to be slow traffic over a number of sequential loops before the system starts setting limits. Usual cause is HGVs overtaking on uphill sections in adjacent lanes at slow speed. In the event of an accident the slowing down of traffic in all the lanes will trigger the system but they can also be set manually.

Not all cameras were working 30 years ago when every camera had to be cabled back to the control room. Digital cameras and wifi means that every camera can be live and as the cameras only record the time and an image of the vehicle they are much cheaper than speed cameras.


One HADECS3 camera can cover up to 5 lanes and these are live 24/7. Anecdotal evidence is that when no reduced speed limit is displayed then they are set quite high - possibly around 85.

Mercdriver

Nearly_Old wrote: »

A couple of corrections:
There are no "trip plates". MIDAS (Motorway Incident And Automatic Signalling) detector loops are located every 500m in every trafficked lane. Its nothing to do with two cars being close and tripping the cameras as it doesn't involve the cameras. There has to be slow traffic over a number of sequential loops before the system starts setting limits. Usual cause is HGVs overtaking on uphill sections in adjacent lanes at slow speed. In the event of an accident the slowing down of traffic in all the lanes will trigger the system but they can also be set manually.

Not all cameras were working 30 years ago when every camera had to be cabled back to the control room. Digital cameras and wifi means that every camera can be live and as the cameras only record the time and an image of the vehicle they are much cheaper than speed cameras.


One HADECS3 camera can cover up to 5 lanes and these are live 24/7. Anecdotal evidence is that when no reduced speed limit is displayed then they are set quite high - possibly around 85.

Newer anecdotal evidence on pepipoo states that on M1/M4/M5 they are set at 79mph, certainly on the newer HADECS being used in those areas.

Car_54

Nearly_Old wrote: »

Not all cameras were working 30 years ago when every camera had to be cabled back to the control room. Digital cameras and wifi means that every camera can be live and as the cameras only record the time and an image of the vehicle they are much cheaper than speed cameras.

I imagine they use mobile phone networks rather than wifi.