Over voltage supply - Any potential problems

Yes. We have 253 volts and certain brands of filaments were going in no time at all. In fact one batch of CFLs also blew but B&Q replaced them for free.

They`re not always entirely reliable as a means for detecting voltage

Its been known for this to happen - are you in a rural area supplied from overhead lines, or are you close to a pole mounted transformer / substation ?

You can ask your supplier to fit a voltage recorder (they`re usually in for about a week) and will record what`s happening properly - and they`re recalibrated on a regular basis to make sure they`re accurate.

On Fri, 14 Jan 2005 21:56:46 +0000, Jason Arthurs strung together this:

Yes. You could get slightly technical and run the lighting off another UPS, then you'd have longer lasting bulbs and some lights for a brief period when the power goes off.

Mildly related obligitary topic drift: Although I would always say buy the best, I've just been looking for a 1000VAish UPS for all my servers and network bits and found some cheapo ones on Ebuyer for £40, can't go wrong with that, as long as it lasts at least 12 months.

Yes.

Try and monitore throughout teh day, and IIRC you can get teh electricity company to downrate teh tap on your transformer to lower it.

I believe its 230v +-10% so max it should be is 253v

Monitoring of my UPS also shows overvoltages, generally they only occur between 11pm and about 5am, so seems to depend on load on the grid, or what mix of generators are in use?

I've not compared the UPS readings to a multimeter reading though, so don't know how accurate it is ...

"Jason Arthurs" wrote | Having plugged in my APC UPS it is reporting 'over voltage'. The test | indicator shows that the voltage is between 248-256v.

That's not significantly over voltage. From the FAQ

- On 1 Jan 2003: the whole EU becomes 230V +/-10%.

So 253V is the maximum.

| Are there any implications for this excess voltage? We've recently | converted most of the house over to energy saving bulbs because | regular filament bulbs were blowing on a regular basis. Is this a | possible symptom?

Filament bulbs are sensitive to overvoltage; most other things aren't within the recommended tolerances.

Owain

That didn't quite happen -- by which I mean the final step in the harmonisation of the tolerances was postponed until [when?]. In the UK we still have 230V +10%/-6%, IOW 216-253 volts.

If you're getting more than 253V then complain. I think they're supposed to fix it within 6 months under their performance targets.

Any *potential* problems with overvoltage supplies?

Currently not, but I know watt you mean. I wouldn't allow this in my ohm, but would conductor thorough check.

You might meet with some resistance from your electricity supplier, but don't put up with any impedance from them.

Dear Henry,

Some resistance from your electricity supplier could be exactly what you need to solve your problem. Let's hope they are very reactive too.

untill 2008 when it will go +- 10%

Ah, thank you. I'm sure I'd read that somewhere but I had forgotten when the change had been postponed to.

Try the ammendments to the 16th Ed of the Wiring Regs.

"Andy Burns" wrote | Monitoring of my UPS also shows overvoltages, generally they only | occur between 11pm and about 5am, so seems to depend on load | on the grid, or what mix of generators are in use?

More likely on voltage drop on the supply cables. Voltage drop varies with load, so overnight when there is little load there will be less drop.

Owain

One of the flats I do work on seems to suffer from over-voltage. (told it was that the supply is uneven due to sharing the substation with the underground). It goes through bulbs much faster than anywhere else and the death of a bulb will likely take out a dimmer (there all switches now).

Yep - in Amendment no. 2 (the one that's mainly about the new colours) it says "1st January 2008 (proposed)." It's still not definite then...

The front panel bar graphs look pretty and give a guide but thats all. I can't remember if the doze software allows you to log the UPS parameters or not (I have some OS/2 software that does), but the readings there are fairly accurate.

I had exactly the same problem as the OP when we moved in here, filament lamps not lasting and UPS in voltage reduction mode the moment it was plugged in. I logged data for a few days, plotted some graphs and rang up the supplier. Man at the door in 2 hrs, measured voltage agreed it was high (but within tolerance, ISTR his meter said

Socket to them if they resist, OK Bill? Then they'll see the light.

NT

We live in Evesham, Worcestershire and are supplied by overhead cables which go back to a rather elderly looking pole mounted substation at the end of the road (the contact number on the transformer is only four digits).

The electricity supply around here is notoriously poor. I used to work for Evesham Technology and every time there was a heavy rainstorm we would lose our power.

Regards, Jason.

That could explain A LOT! ;-)