How accurate are average speed cameras

ebbsy

I've been at 9 points, now back to 3, and guess what ?

It was nobodys fault except my own.

Red Silurian

If I was in your shoes and was 100% sure that you weren't speeding I would contest it. You could pay a solicitor a few quid to represent you or just take a couple of hours off work.

If you had any proof that you were not speeding, your own dashcam footage for example showing Junction 26 and Junction 27 in the same clip it should suffice. The junctions are a little over 14km apart so if you have a video of you doing this in more than ~7 minutes on that date you have solid evidence.

mickdw

https://www.boards.ie/discussion/comment/121452753#Comment_121452753

When you were on 9 points and no doubt being super aware so that you didnt get anymore points, if you got a letter to say you were speeding again and heading for a ban, would you challenge it or take the spell off the road?

https://www.boards.ie/discussion/comment/121452717#Comment_121452717

I did not know that !

That may explain it. I have large feet in boots, so could have been pressing down on it.

Olympush

You could ask to see a calibration cert for the camera - if it’s more than 6 months since it was last calibrated, you may have a case.

Oscar_Madison

https://www.boards.ie/discussion/comment/121453572#Comment_121453572

You did say you were overtaking a couple of folk - easily done then thinking you were still driving at 120 when in fact it was well over that - a pain I know - the good news is most insurance companies don’t care about 3 penalty points for speeding as long as you tell them it’s the thought of 3 years avoiding another 3 penalty points to make six which will make you even more cautious - I’m nearly finished my 3 year “sentence” 😀- it does focus the mind that bit more - I think you’re just unfortunate but just shows you need to be proactive regardless of what support technology you have.

ohnonotgmail

https://www.boards.ie/discussion/comment/121453580#Comment_121453580

There is no requirement for them to prove that speed cameras are working correctly. With average speed cameras calibration does not apply. They do not measure speed. they only measure the time that you passed both cameras and your speed is calculated from that.

https://www.irishstatutebook.ie/eli/2010/act/25/section/81/enacted/en/html

monkeybutter

https://www.boards.ie/discussion/2058325588/how-accurate-are-average-speed-cameras

1. Use GPS to verify limiter is working. Never seen a speedo to under read by 10kph
2. Request both pictures. You would need this if you happened to go to court. If they tally up..

They should be providing this on the FPN really. They can't expect you to turn up to court without having seen it.

https://www.boards.ie/discussion/comment/121453627#Comment_121453627

If you can go over the limiter then yes, I could very well have gone above it. The overtaking not so much as both vehicles were going well below 100 !

I actually, naively, thought that the limiter stopped you from going over the set speed, so I may have been going over it without realising.

mikeecho

https://www.boards.ie/discussion/comment/121453580#Comment_121453580

Nope.

They don't have to prove that the device was calibrated or accurate, there is a presumption that it is accurate.

You can ask for the calibration cert , but it will be of feic all use.. anyway, they are all kept within calibration.. it's part of the contract from the supplier.

ebbsy

https://www.boards.ie/discussion/comment/121453453#Comment_121453453

To be fair, a very good question.

Calahonda52

the distance is 13k

at 120 6.5 minutes

at 129 6.0465

so 27.2 seconds

looking further at the numbers, my guess is you were never under 120

This content has been removed.

Miscreant

https://www.boards.ie/discussion/comment/121456021#Comment_121456021

We don't do graduated speeding fines here. I would imagine that 120 in a 60 zone might be treated as dangerous driving and that is a whole different kettle of fish.

This has absolutely nothing to do with the OP though......

This content has been removed.

I have my car back as of yesterday evening.

First thing I did was take it out to the motorway and test the speedo. It is actually out. I had both mine and my wife on sat nav and when I set the speedo to 120 the sat navs had me going 126

Kimbot

https://www.boards.ie/discussion/comment/121456403#Comment_121456403

So if GPS is showing you do 126 then your speedo if correct should show around 130ish normally.

https://www.boards.ie/discussion/comment/121456468#Comment_121456468

No, I think the speedo is showing less than what I am actually doing. Both satnavs on our phones had me at 126-127 on a stretch of motor way, and it was on cruise control with the limiter set at 120.

I rang them this morning and the garage said it might need to be re-calibrated.

Kimbot

https://www.boards.ie/discussion/comment/121456489#Comment_121456489

yes thats what I meant, you speedo should have been reading 130+

https://www.boards.ie/discussion/comment/121456504#Comment_121456504

Oh sorry, yes it should have been.

The garage did say that to me that there is usually around 5KM less built in, so mine seems to be the other side , of course !!!

Kimbot

https://www.boards.ie/discussion/comment/121456518#Comment_121456518

If your speedo is out then get the garage to write some form of letter to help with your appeal if possible.

https://www.boards.ie/discussion/comment/121456535#Comment_121456535

I will ask for sure.

Nothing ventured !

Miscreant

@Skyrimaddict Are you sure your car has it's original wheels? What make and model is it? I know you said in an earlier post that you have 18in wheels but they may have been changed by a previous owner from 16in or 17in

The speed discrepancy is quite large though between your speedo and the GPS. Something like 10-12Kmh of a difference in reality (from under-read to over-read) so it may not be down to wheels alone. The car definitely needs to be checked out, regardless.

Best of luck with any appeal you put through.

Kimbot

https://www.boards.ie/discussion/comment/121456609#Comment_121456609

Opel Insignia 2020, standard wheels according to google are 18's

Henry Ford III

So with a 120kph limiter engaged you got a ticket for 129kph average?

There's something wrong there somewhere. I'd imagine the speed cameras are accurate.

Alun

https://www.boards.ie/discussion/comment/121456618#Comment_121456618

18" wheels says nothing ... the tyres you have on them could have a huge variation in aspect ratio and therefore sidewall height, rolling radius and ultimately speedo inaccuracies.

What tyres are on it now, and what are the standard tyres as shown in the manual or the tyre inflation sticker?

Once you know this you can use an online tyre calculator to see the differences including the speedo difference.

https://tire-calc.com/

https://www.boards.ie/discussion/comment/121461271#Comment_121461271

As above.

magicbastarder

https://www.boards.ie/discussion/comment/121456535#Comment_121456535

don't think this would work, and in fact would weaken their case probably - it in no way refutes the evidence that they were speeding; ignorance is no defence; and 'i broke the law because i had a faulty car' will not gain any sympathy whatsoever.

legally your speedo is allowed overstate your speed, within specific parameters. it's not allowed understate your speed, so announcing that your car is illegally reading the wrong speed might not be wise.

Kimbot

https://www.boards.ie/discussion/comment/121461915#Comment_121461915

Well lets just say that the car is all factory, factory wheels tyres etc. Why should the OP be penalised if it can be proven the car was sold with a faulty speedo. TBH how many people actually go and get their speedo calibrated, I would wager not many at all so if I were to buy a car tomorrow, Take it from the showroom and drive through the average cameras on cruise control @ 120kmph but it picks me up @ 135kmph then how am I to know I am speeding when the car itself is telling me I am not?

ohnonotgmail

https://www.boards.ie/discussion/comment/121461937#Comment_121461937

none of that is a defence in court. if the vehicle is fault then his recourse is with the dealer/manufacturer.