SM - Just had the meter reader round again

[Tufnell Park]

It doesn't work that way, normally when a meter reaches the end of it's certification period, that meter will be removed from service and a new one installed.

[Robin]

That's how I understand it (subject to it being 10 years at most when new if it's an induction meter).

I never said there were no out-of-certification meters out there!

But it may be more complicated than Schedule 4 suggests/I understand as I know someone who worked as a meter reader for a few months while between his "proper" jobs. He tells me now that the 200.16 wasn't on the "must be replaced" list - unless it was one of the models which would run backwards. Seems they won't if "H" is in the meter type.

[Tufnell Park]

No that is not what happens in practice.

A meter which has reached the limit of it's certification period would invariably be replaced with a new meter. The 'old meter' would then be returned either to a meter testing facility for accuracy limit testing and possible recalibration or be scrapped (dependant on condition).

[Robin]

As I read it what Dave was asking was whether - to unpack it further FTAOD - the following was possible:

a. meter model X certified for 10 years b. meter M of model X is fitted in 1990 c. meter model X is recertified, probably more than once, to end up to end up certified for 40 years d. so meter M fitted in 1990 is still within certification in 2018

I feely admit I've never been responsible for meters at any point in the chain. But if that's not what happens I am puzzled as to why the people responsible for certification - the Office for Product Safety and Standards - tell the public:

"Subsequent in-service surveillance monitoring through the national sample survey or In-service testing can result in the certification life of a meter type being either extended or reduced."[1]

I note also that in the original regs. in 1998 Schedule 4 showed S200.16 meters had a life of 25 years where they now have a life of 40 years. Similarly the C11B2 has gone from 20 to 30 years.

[1]

[Tufnell Park]

My metering experience was gained over 30 years working in the ESI at all levels.

This is a 'catch all' clause which provides for the facility to reduce or extend meter certification periods in some cases in the light of in service experience.

In practice if a meter was installed in 1990 with a 20 year certification period then it would have be changed in 2010 unless it could be proved by rigorous in-service trials that the meter type maintained its accuracy well beyond 20 years. However i doubt the certification would be extended by as much further 20 years.

The whole point of meter certification is to ensure accuracy within specified limits throughout the in service life of *every* meter, something batch testing cannot do.

Meters installed today may well be capable of certification for up to 50 years but that is not what the OP or i was discussing.

I note also that in the original regs. in 1998 Schedule 4 showed S200.16

[Dave Liquorice]

plonked

if that is the case it's bonkers and one may as well not bother with any form a certification at all.

certification.

Is a spinning disc induction meter...

Is also a spinning disc meter.

Curiously this is electonic, with the shortest certification period.

No "H" here... So in theory the '67 meter ought to be replaced because it's 11 years out of certification and it can run backwards.

[Tufnell Park]

Most meters installed in domestic premises in 1967 would have been replaced by now.

However gaining access to properties where the meter is installed inside the property (as opposed to an external meter box) can be problematic sometimes, to say the least.

[Dave Liquorice]

plonked

But yes meters replaced due to being out of their certification period would have been returned, checked over, tested and then recertified or scrapped if they failed to meet the mark along the way.

I guess these days, with cheap electronics and the supply companies not the DNO being responsible for the meters, it's not economic to spend time overhauling and testing mechanical ones and they just go straight to scrap. All the same the certifaction still applies and meters out of certifcation should be routinely replaced.

[Tufnell Park]

Yes that is what should happen!

[Dave Liquorice]

backwards.

We've been here 20 years, never had a meter changed.

No supplier has ever even asked to change any meter. That is until e.ON contacted us last week wanting to fit a "Smart Meter". That says something about the Smart Meter roll out...

[Dave Liquorice]

Within limits that is acceptable and to a certain extent pragmatic.

In 1998 the 1967 meter had been in service 31 years so 6 years over due then... It's now 11 years over due for replacement.

This one 2 years under in 1998 but now 8 years over due.

[Tufnell Park]

I would say that is unusual in my experience, of course if there was an external meter box at your property you might not be aware the meter had been changed. (Although i suspect this not applicable in your case).

[Robin]

Maybe, though I have already given you an example of a meter extended by

15 years from the 1998 Schedule.

I'm having trouble reconciling that with Regulation 9 (Batch testing) which provides for an examiner to do just that - i.e. "Where...a number of meters have been submitted...the examiner has examined and tested a sufficient number of the meters to satisfy himself that it provides a reasonable test of all of them...he may issue a certificate in respect of all the meters..."

[Tufnell Park]

Depends what 'a sufficient number' is i suppose.

[Martin Brown]

There is that "no signal" problem and/or meter inside a Faraday cage.

And then there is the crazy situation where the same guy comes round the same places on different days with different supplier company hats on! I know this because I am a keyholder for the Village Hall and the guy who comes to read that comes to me first. It is quite predictable.

We aren't in the Dales but the mobile signal here is quite poxy outdoors and almost non-existant inside a solid wall Edwardian building.

[Robin]

JOOI when you say "the 1967 meter" etc are those the dates on the seals?

And for what little further anecdotal evidence is worth, the induction meter here was not changed in the 28 years before it was replaced at our request a few years ago. And an elderly friend bought a new-built house in the 1990s which had the same meter until she moved in care in 2015 - with a label by it which I wish I'd paid more attention to since it said something about certification in 2006.

[Dave Liquorice]

No, the two digits in the first part of the meter number.

eg S67M: S = Sangamo, 67 - year of certification, M - Norweb.

I can only find a wonkypedia reference to decoding that part of the number. Having said that theer are number fo meter images that have a certified stickers and the year on the sticker that corresponds with the year in the meter number. Also the years on our meters tie up with when the various supplies would have been installed.

[Robin]

OK, thanks, that sinks my soggy straw.