Speed camera tolerance change?

DaveyDave

Checked mine with GPS there, seems to be 3-4kph difference.

Henry Ford III

Isambard wrote: »

the gardai issue the fines foe gosafe captures.

The penny dropped, eventually. My contact is an ex Garda who would have pretty detailed knowledge of the workings of the system.

Isambard

DaveyDave wrote: »

Checked mine with GPS there, seems to be 3-4kph difference.

at what speed? Obviously it would be less than that at 30km/h and a lot more at 120km/h. I always contend the inaccuracy would be a percentage ,

Del2005

Isambard wrote: »

at what speed? Obviously it would be less than that at 30km/h and a lot more at 120km/h. I always contend the inaccuracy would be a percentage ,

It would be easier for a manufacturer to just display the speed plus 3km/H, as that means they comply with the EU regulations in 30 zones, rather than programming the ECU to over state by a percentage of the speed.

i57dwun4yb1pt8

Isambard wrote: »

at what speed? Obviously it would be less than that at 30km/h and a lot more at 120km/h. I always contend the inaccuracy would be a percentage ,

it is
its +5 % in VAG cars anyway at any speed

so it checks your speed and adds 5% for the speedo that you look at

DaveyDave

Isambard wrote: »

at what speed? Obviously it would be less than that at 30km/h and a lot more at 120km/h. I always contend the inaccuracy would be a percentage ,

60kph. I'll see what it's like at 30, 50 and 80 if I can.

TheChizler

Isambard wrote: »

at what speed? Obviously it would be less than that at 30km/h and a lot more at 120km/h. I always contend the inaccuracy would be a percentage ,

It all depends on tire pressure, wear, speed, accuracy of whatever is doing the measuring, even before you get to adding an intentional offset. Probably off by some second order exponent equation if you want to get technical.

deandean

If I got a ticket for doing 52 in a 50 zone I'd take it to court and take my chances in front of the Judge.

I'd argue that it's unreasonable to be fined for being 2km/h over the limit. Cars are driven by people, not by robots.

TheChizler

deandean wrote: »

If I got a ticket for doing 52 in a 50 zone I'd take it to court and take my chances in front of the Judge.

I'd argue that it's unreasonable to be fined for being 2km/h over the limit. Cars are driven by people, not by robots.

"€1000 fine and 5 penalty points, next!"

i57dwun4yb1pt8

deandean wrote: »

If I got a ticket for doing 52 in a 50 zone I'd take it to court and take my chances in front of the Judge.

I'd argue that it's unreasonable to be fined for being 2km/h over the limit. Cars are driven by people, not by robots.

yes but the point is 52 means you were doing 55 on the speedo ,
they know this , so imply you were consciously over .

josip

Del2005 wrote: »

It would be easier for a manufacturer to just display the speed plus 3km/H, as that means they comply with the EU regulations in 30 zones, rather than programming the ECU to over state by a percentage of the speed.

It would the same amount of effort in both cases,

DisplaySpeed = ActualSpeed + 3
or
DisplaySpeed = ActualSpeed * 1.05

unless I've misunderstood your point?

GreeBo

DaDumTish wrote: »

yes but the point is 52 means you were doing 55 on the speedo ,
they know this , so imply you were consciously over .

That would imply they would fine you for doing 49 as your speedo read > 50.


More likely the limit on the road was 30.

OP, what road are we talking about here?

Del2005

josip wrote: »

It would the same amount of effort in both cases,

DisplaySpeed = ActualSpeed + 3
or
DisplaySpeed = ActualSpeed * 1.05

unless I've misunderstood your point?

Your right, I was over thinking it.

i57dwun4yb1pt8

GreeBo wrote: »

That would imply they would fine you for doing 49 as your speedo read > 50.


More likely the limit on the road was 30.

OP, what road are we talking about here?

i think they let you away with 51 but 52 means you were at the speedo midpoint so tough luck

this is on a car with 5% leeway

Avatar MIA

GreeBo wrote: »

That would imply they would fine you for doing 49 as your speedo read > 50.


More likely the limit on the road was 30.

OP, what road are we talking about here?

It was a 50 zone, but I can't remember if they told me the road they were on.

RiseToMe

I've posted about this before on here, but in terms of "tolerances and allowences" when you set up measuring equipment you need to consider the entire set up including what you are measuring and calculate a "measurement of uncertainty".

In this case there the measurement of uncertainty will be affected by the calibration accuracy of the equipment, there will be an allowance for the user and an allowance for any small deviations from set up. So if they determine the above has for example, a +/-5% uncertainty then this is your leeway. If they have improved the "true reading" of the equipment, the uncertainty is adjusted.

If you get done for traveling at 52kmph in a 50 zone, the calculation of your speed will have already allowed for an uncertainty of measurement, so the absolute SLOWEST you possibly would've been travelling is 52kmph, hence the ticket.

mikeecho

I don't believe that a ticket was issued for 2km over.

Post a pic of the letter.. with identifying info hidden.. otherwise, I call Büllshīt

ED E

RiseToMe wrote: »

I've posted about this before on here, but in terms of "tolerances and allowences" when you set up measuring equipment you need to consider the entire set up including what you are measuring and calculate a "measurement of uncertainty".

In this case there the measurement of uncertainty will be affected by the calibration accuracy of the equipment, there will be an allowance for the user and an allowance for any small deviations from set up. So if they determine the above has for example, a +/-5% uncertainty then this is your leeway. If they have improved the "true reading" of the equipment, the uncertainty is adjusted.

If you get done for traveling at 52kmph in a 50 zone, the calculation of your speed will have already allowed for an uncertainty of measurement, so the absolute SLOWEST you possibly would've been travelling is 52kmph, hence the ticket.

Worth noting the informational radar speed signs are rated to +/- 3% so its safe to assume the margin in six monthly calibrated guns and vans is more like 1%.

RiseToMe

ED E wrote: »

Worth noting the informational radar speed signs are rated to +/- 3% so its safe to assume the margin in six monthly calibrated guns and vans is more like 1%.

I didn't say it was 5%, I said for example. Furthermore that 5% was based on total uncertainty, you need to consider the other aspects such as user and set up in your overall uncertainty (all relative uncertainty) as well as allowing for expanded uncertainty using coverage factor k in order to determine your confidence level. All of which will see that 1% rise much further.

mikeecho

mikeecho wrote: »

I don't believe that a ticket was issued for 2km over.

Post a pic of the letter.. with identifying info hidden.. otherwise, I call Büllshīt

Also calling nonsense on this thread. No ticket was issued for 52 in a 50. I doubt such a ticket was ever issued in the country's history.

deandean wrote: »

If I got a ticket for doing 52 in a 50 zone I'd take it to court and take my chances in front of the Judge.

I'd argue that it's unreasonable to be fined for being 2km/h over the limit. Cars are driven by people, not by robots.

TheChizler wrote: »

"€1000 fine and 5 penalty points, next!"

There isn't a judge in the country that would do you for 52 in a 50. Which is why such a ticket wouldn't be issued.

These kind of threads always remind me of a local newspaper's court section, where a person was done for, I believe, 59 in a 50. Person explained that although it was a 50 zone, it was not a built up area, was not a housing estate or town, was a well-paved, wide road, at night with little traffic and with good lighting.

The judge replied that his courtroom was "a court of law, but also a court of justice", and dismissed it, letting your man go free. He said it'd be different if the person were doing 59 in a 50, in a built up area with people around.

Now, I know these things vary from judge to judge, but I'd definitely take my chances in court if I got done for 52 in a 50. Judge would give out to the Garda for wasting his time.

Avatar MIA

mikeecho wrote: »

I don't believe that a ticket was issued for 2km over.

Post a pic of the letter.. with identifying info hidden.. otherwise, I call Büllshīt

As I said, it's literally a friend of a friend that said it. I personally believe them, and no I won't be asking them to request proof they are not lying.

Deleted User wrote: »

Also calling nonsense on this thread. No ticket was issued for 52 in a 50. I doubt such a ticket was ever issued in the country's history.

Likewise, but I will pass on the useful information subsequently posted.

josip

I also find it hard to believe anyone was done for 52 in a 50.
What's the lowest over the limit anyone on here has ever been done for?
I've gotten one for 60 in a 50.

Caliden

OP I thought it was yourself personally that got it.

Sounds harsh but this 'friend of your wife' could be easily saying 52 which in actual fact it's 57 or something to make themselves feel hard done by

Avatar MIA

Caliden wrote: »

OP I thought it was yourself personally that got it.

Sounds harsh but this 'friend of your wife' could be easily saying 52 which in actual fact it's 57 or something to make themselves feel hard done by

Possible, but I personally believe her.

Zubeneschamali

josip wrote: »

What's the lowest over the limit anyone on here has ever been done for? I've gotten one for 60 in a 50.

110 in a 100 zone, Garda speed van.

josip

josip wrote: »

I also find it hard to believe anyone was done for 52 in a 50.
What's the lowest over the limit anyone on here has ever been done for?
I've gotten one for 60 in a 50.

My brother was done for 59 in a 50 (note: not the same '59-in-a-50' story i posted above).


He claims there was no speed van, and he wasn't stopped by a Garda, so unsure of the method used (i know the area he got done, and I often see the 'hairdryer out the window' Garda car, but i presume they have to stop you, so I imagine they just set up the tripod this time around and nailed him).




He didn't contest it as he already has points on his license. But that's the lowest I've seen, personally (he was driving my car, so letter came to me, so i seen it first-hand).

mgbgt1978

57 in a 50. 2 1/2 years ago .....GoSafe at 6:22 AM. My own fault. I saw him well in advance, but was convinced I was in a 60 zone (which I now know starts about 50m beyond where he was) and eased off from an indicated 63 down to 60.
The fine is long forgotten, but 3 years is a long time for points to stay on your Licence .

ED E

RiseToMe wrote: »

I didn't say it was 5%, I said for example. Furthermore that 5% was based on total uncertainty, you need to consider the other aspects such as user and set up in your overall uncertainty (all relative uncertainty) as well as allowing for expanded uncertainty using coverage factor k in order to determine your confidence level. All of which will see that 1% rise much further.

Only intending to add to your post, not contradicting it.

Irish Steve

Just in passing, it is a fallacy that all speed indications over read significantly. We've 3 different vehicles in the immediate family, and I drive all 3 at different times, and have checked the speedo's against a GPS, and the GPS is active all the time in one of the 3. The worst is a Fiat Seicento, to be doing a true 120 Kph, the speedo has to be showing 135 Kph, which is outside the tolerance that's supposedly meant to be there, but that is most likely down to wear on the tyres, (they're small, so turning fast), and the age of the vehicle, but realistically, it's not on Motorways that often, so not an issue as such. It's proportionally wrong at lower speeds as well, but that's no bad thing.

The other 2 vehicles are very much not inaccurate, the Isuzu crew cab and Citroen Picasso are both accurate at less than 2 Kph over at 120, 120 on the GPS is under 122 on the dial or the display, so they both have to be treated with respect to avoid going over limits, and the size of the tyres and wear make very little difference to the indicated speed compared to the actual speed. They both over read very slightly, so that is on the right side to avoid problems, but is it very much not safe in either of them to work on the "they allow 10%" that it trotted out on a regular basis by some people, 132 indicated on the Picasso would be well in excess of 120 true.

Having said that, I have also checked a number of vehicles with the GPS, and there are indeed some that are very much over reading, but as I don't own them, or drive them on a regular basis, there's no point doing anything about it, other than to let the owner know that there is an error in the indicated speed.

The worst I've seen was a few years ago, a family member had an automatic Escort that seemed to take for ever to get to places, and when we checked it out, we found that an indicated 70 Mph (UK car and on UK roads) was an actual 56 Mph, so it was well wrong. On investigation it was found to have a wrong speedo drive gear in the adapter unit on the gearbox, which was replaced, and restored a more realistic indication.

The_Kitty

Henry Ford III wrote: »

The penny dropped, eventually. My contact is an ex Garda who would have pretty detailed knowledge of the workings of the system.

So is it gosafe or the guards that go through the photos and issue the fines?