Overvoltage

glennevis

OP unless you have an in-date calibration certificate for your data logger, your claimed voltage figures could be rejected as inaccurate.

[Deleted User]

Yes I do. All my test equipment is calibrated and certified. However certified or not they will not accept my readings as proof and to be fair you wouldnt expect them to. They will install their own data logger, hopefully soon.

Robin9

I suspect your data logger is of a higher spec than that of the distributor.

When I was doing these investigations my main concern was of wildly fluctuating voltage - an indicator of deteriorating joints. Then we used an ink pen on a paper chart.

"High" voltage is less of an issue and I suspect an alteration to the transformer tapping will be required.

[Deleted User]

Robin9....ha very good. Well I have to admit when I compared my Avometer with the meter the engineer had I did have a similar thought. You are spot on in that altering the tapping of the local transformer is exactly what he said he thought was required. I fully accept that the grid company and people reading my comments have to question the accuracy of my measuring equipment but I am totally surprised by the attitude that a supply voltage above statutory limits is somehow acceptable. Anyway, thanks for your input.

System

Deleted_User wrote: »

Robin9....ha very good. Well I have to admit when I compared my Avometer with the meter the engineer had I did have a similar thought. You are spot on in that altering the tapping of the local transformer is exactly what he said he thought was required. I fully accept that the grid company and people reading my comments have to question the accuracy of my measuring equipment but I am totally surprised by the attitude that a supply voltage above statutory limits is somehow acceptable. Anyway, thanks for your input.

Are you perhaps conflating two issues here? If over-voltage was acceptable then the responsible organisation would just say 'tough' and work away, which it clearly isn't doing. The issue which is concerning you, and would concern most of us, is whether the over-voltage situation has led to damaged equipment and who should pay? This is from a post on the IET forum (somewhat dated but the precedent is there):

Quote: Update for today: The HV Transformer is to be replaced as it has a earth/neutral fault.
UK Power Networks today confirmed that this has been pushing high voltages since 2002!!!

They have admitted liabilty and we have been asked to submit a claim for our losses.

I just can't imagine how these levels of output were not picked up by the systems that monitor them.
All we know is that it is without doubt the fault of the supplier and a failing transformer.

BTW! The new toaster worked without blowing up this morning. First time in 5 years LOL Unquote

I did get compensation for my late Mother some years back. I was in the 'fortunate' situation that the event impacted on a number of properties in the area and the local MP was on the case.

reeac

I would have thought that any incandescent lights would soon pack up if subjected to 260 rather than 240 volts. Have you seen such excessive failures?

[Deleted User]

Morning. Well as I said the issue arose as a result of the failed UPS which made me check voltages. I am waiting to hear back from the company, UPN, to see what their action if any has been. Voltages still seem to exceed the 253volts at times but not by as much as before. So yes the company appear to be concerned but here looking for guidance on the statutory aspects some people appear to be unconcerned. Interesting in the piece you have kindly sent is the section about monitoring as my understanding both from research and the engineer who arrived is that they don't routinely monitor. If that's true in this day and age well I am surprised.

[Deleted User]

Morning. Interesting that you should say this because first of all I replaced all such devices some years back however I go through kettles like they are going out of fashion. They never last a year sometimes just a few months. In fact friends laugh about this as they know I like my tea. I am regularly returning kettles under warranty. In the last 12 years I suspect I have probably had at least fifteen kettles. It now makes me wonder.

[Deleted User]

Deleted_User wrote: »

My issue is with overvoltage and I still continue to wait for a satisfactory answer to my question which is why when the regulations clearly say that the maximum uk voltage is 253volts are the authorities and most people on here so relaxed about it?

You have had an answer, the excess is fairly small, so if there's no benefit in fixing it they're not going to spend money for no good reason.

The difference between 253 and 260 is just 2.8%, but the reliability of electronic components is at its best when they operated well below their rated maximum. The failure rate is highly non-linear, climbing rapidly after the stress exceeds 50-60% of the rating, so if the components in your supply are at 97.2% of their maximum on 253V it's already an unreliable design.

You won't find any of the power supplies I've designed as marginal as that.

Deleted_User wrote: »

a data logger is due to be installed at my house and I am still waiting for this to be done.

So they are doing something about it, if they find the excess is significant, presumably they'll do something about it.

Deleted_User wrote: »

my understanding both from research and the engineer who arrived is that they don't routinely monitor. If that's true in this day and age well I am surprised.

They won't monitor if the cost of monitoring exceeds the cost of not monitoring.

Deleted_User wrote: »

Morning. Interesting that you should say this because first of all I replaced all such devices some years back however I go through kettles like they are going out of fashion. They never last a year sometimes just a few months. In fact friends laugh about this as they know I like my tea. I am regularly returning kettles under warranty. In the last 12 years I suspect I have probably had at least fifteen kettles. It now makes me wonder.

Of all the appliances in a house, the kettle is about the least sensitive to overvoltage.

[Deleted User]

jack.....you simply fail to understand that this is a statutory matter, it's laid down in law that the maximum is 253volts. They have a duty not to exceed this even if you say that 6 or 7 volts is nothing in the scheme of things. You can go on about this until the cows come home, but 253v is the maximum they should be making available irrespective of anything else.

Monitoring. Well to do anything costs more than doing nothing at the time, that I would have thought is painfully obvious.

Kettles, I was just stating the fact when asked about conventional lamps that's all, no need to make an issue out of it.

Finally, just spoke again to UPN and they said that 253v and above is a serious issue for them and a data logger is going to be installed to check the present situation. It seems that transformer tappings have been changed. So that seems to support the fact that +6v is an issue.

So the facts appear to speak for themselves.