Reasons for devices failing throughout the house

Just because you might be paranoid doesn't mean they aren't out to get you. :)

6 items in a week is probably not chance. There is something going on.

Has anyone determined how they failed? My guess would be high line voltage or line voltage spikes.

Check the AC line voltage on the circuits where these devices were.

It's possible there is an open Neutral or a bad connection to the Neutral resulting in excessive AC voltage on some circuits. Do you experience unusual dimming, or more significantly, brightening of lights when a load kicks in like a fridge or A/C compressor? The latter would be an indication of a Neutral problem.

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Thanks Sam.

Well, at least one hasn't failed -- just fixed the satellite box -- but rest are dead. I'll get an engineer in. We bought a new fridge and freezer in the last couple of weeks but never thought they could be causing this. I think I need to get it all checked out.

Hadn't noticed the lights but it could well be the case that they dim. And at least I have someth> snipped-for-privacy@yahoo.co.uk writes:

He's in the UK not the USA so you can rule out that problem. We don't have centre tapped 240V.

Graham

Do you by any chance live in a village with old overhead PMR mains supply ? Just a thought as a friend of mine suffered a virtually identical problem to this, which ultimately turned out to be an intermittent neutral connection, as someone else has suggested, back at the pole mounted transformer. This was apparently resulting in the mains intermittently shooting up to phase-phase voltage of 440v. I'm not sufficiently au fait with how power distribution networks work, to tell you exactly how this occurs, but when the electricity board came out and sorted this problem, the multiple equipment failures stopped.

Arfa

AFAIK nothing like that, Arfa. Like Graham said, I'm in the UK. Medium-sized town. Nothing out of the ordinary. This might sound really dumb, but I wondered if a spike could get around surge protectors, via something like a cable modem...

centre

That's no guarantee at all. I'm not an expert in power distribution, but a failing neutral can wreak havoc even without centre tap.

His 240 volts are likely to be one leg of a 380 or 400 volts

3-phase system. Kill it's neutral and the lights all shine. Briefly :-)

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Most likely electrical problems in the house, causing voltage spiking. This should be checked out by a specialist in analysing electrical problems. The power company should be equiped with the proper equipment to do these types of tests.

Jerry G.

snipped-for-privacy@yahoo.co.uk wrote:

Did you happen to have a thunderstorm anytime up to two weeks before things started failing?

How? Remove the neutral and you have no current flow in a single phase system like all houses in the UK have. You only get your '380 or 400 volts' between phases in a three phase installation.

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    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.

Yes but remember that electricity is often distributed as far as your street in 3 phase - your house might be on L1, the next house on L2 and the next L3. Of course, losing the neutral connection WITHIN YOUR HOUSE will not cause an overvoltage situation, simply a power failure. However, losing the neutral further up the distribution system e.g. at the pole transformer or substation could cause overvoltage because the neutrals of all the houses will still be commoned together and the houses are not all fed from the same phase. Therefore you could have

415V across yours and your neighbours house installations, the common neutral serving as the link. What you now have is a potential divider in electronics terms and unless both houses had absolutely identical appliance loading, one house is going to get a greater share of the voltage than the other possibly resulting in damage to appliances.

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Tim Phipps

replace "invalid" with "uk" to reply by email

Yes, this was in the UK too - hence the 440v phase-phase. Many villages still have overhead distribution PME systems in use, which is why I was querying the point. Pole mounted transformers are not the exclusive preserve of power distribution in the US. Until a couple of years back, when it was finally put underground, the farm behind me was fed from an 11kV pole mounted transformer at the bottom of my neighbour's garden. Another poster further up the thread, has explained exactly how the neutral problem can occur, even with modern underground and substations, so it's still quite possible that this is the cause of your problem.

Arfa

My first impression was to ask how the weather had been the last week or two; but since he's in England...no need.

jak

surge protectors do not always help. if you had a near hit of a thunder shower the EMF from it can have been induced to cause the speakers to fail since the speakers have a magnetic coil in it and could have absorbed too much EMF, but since lightning is a rather short burst i would not say that is it,.. the other problem could be a loss of ground from your service causing items that are plugged in to get twice as much voltage as it should or some one has recently done some rewiring in the house and has the lines backwards!

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Oh Jak ! That's below the belt ! For the last couple of weeks, the weather here has been glorious ... d;~}

Arfa

Might have been in your part of England, but not throughout. ;-)

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    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.

You mean the sky was a lighter shade of gray?

Actually, I have experienced some very nice weather in Blighty...one afternoon.

jak

But we have proof of the current weather. Wimbledon tennis. Normally rained off, but only on Monday so far this year.

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    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.