Power buzzing after 5pm, help please!

[BS3036]

I assume (in my ignorance) that three phases are in use, and maybe the 2 buzzing 'fuse boxes' are on the same phase.

I'm not sure if I gave the impression that 'interference' has to be electromagnetic wave interference. A non EMC conformant appliance can inject current into a phase which can cause problems for users of that phase in the vicinity. The cable can give rise to detectable electromagnetic wave signals which can provide a way to localise the fault.

However this didn't turn out to be helpful in this case.

Can you talk to the user of the other buzzing circuit to see if they have problems?

Can you determine from the wiring which meter uses which phase? And if the 2 buzzing ones are on the same phase?

 

[tim west]

Your psu's buzzing is one thing but damaging them is another, unless its unrelated of course.

Were the electricians at your premises when the buzzing was occuring? Did they check your supply during this period?

Suspicions from the above post mentioning the three phase supplies maybe the neutral is loose(intermittent) and occasionally your equipment is seeing a potential 415v ie check that any of your neighbours especially the one fed by the other meter 5/8? isnt having the same problems with equipment failing, a main neutral fault(open circuit) can cause appliances to become series'd up across two phases with adjacent flats fed off different phases to yours.

 

[aptsys]

Any chance you can take a few pictures of the set-up?

 

[Softus]

Unfortunately I can't get hold of an oscilloscope.

That's just nonsense. You can easily afford this rudimentary 'scope, because it's gonna cost you more to get an electrician to come and find the fault.

You can't analyse what you can't measure. If you can't measure what's going on with your power supply then you're only hope is to wander around and make arbitrary guesses. Oh hang one; you already did.

 

[willcocks]

Unfortunately I can't get hold of an oscilloscope.

That's just nonsense. You can easily afford this rudimentary 'scope, because it's gonna cost you more to get an electrician to come and find the fault.

You can't analyse what you can't measure. If you can't measure what's going on with your power supply then you're only hope is to wander around and make arbitrary guesses. Oh hang one; you already did.

You realise that in rented accomodation paying for an electrician to come out would be stupid? I cannot afford 80 quid at the moment.

Yes the electricians were all here when it was buzzing. They did have a look in the cupboard but I'm pretty sure they didn't bother checking in any detail as the "meters" are not their responsibility and the wiring in the house is okay. YEDL didn't check the wiring in the meter cupboard either. I will get some pictures later, not sure if you can tell what phases they are on - atleast I cannot.

 

[Softus]

You realise that in rented accomodation paying for an electrician to come out would be stupid?

Were we supposed to guess that this accommodation was rented?

I cannot afford 80 quid at the moment.

But apparently you can afford to replace anything that gets damaged by this RF storm that you're suffering.

Yes the electricians were all here when it was buzzing.

So who paid for these electricians, and was that person motivated to find the problem?

If you unplug every appliance in the property, and plug in a TV taken from somewhere else where it doesn't buzz, and it then buzzes, then you can be sure that you're not causing the problem.

Armed with that certainty, you've done all that you reasonable can in a rented property to solve the problem. At that point it's down to the landlord to find the problem, and you should put that in writing.

Having done that, based on the information that you've revealed so far, there are only two non-stupid courses of action: either you move out, or you stay there and dock the rent until the problem is solved.

 

[vsynth]

Having rented in the past quite a bit I know that most short term (6 month) renting arrangements state that the tenant "has the right to quiet enjoyment of the property" and it sounds like you are not getting that.

Where in the UK are you willcocks, I would love to come round and connect a scope to your supply, I am an electrical/electronics engineer.

 

[willcocks]

You realise that in rented accomodation paying for an electrician to come out would be stupid?

Were we supposed to guess that this accommodation was rented?

I cannot afford 80 quid at the moment.

But apparently you can afford to replace anything that gets damaged by this RF storm that you're suffering.

Yes the electricians were all here when it was buzzing.

So who paid for these electricians, and was that person motivated to find the problem?

If you unplug every appliance in the property, and plug in a TV taken from somewhere else where it doesn't buzz, and it then buzzes, then you can be sure that you're not causing the problem.

Armed with that certainty, you've done all that you reasonable can in a rented property to solve the problem. At that point it's down to the landlord to find the problem, and you should put that in writing.

Having done that, based on the information that you've revealed so far, there are only two non-stupid courses of action: either you move out, or you stay there and dock the rent until the problem is solved.

The letting agency have washed their hands of us as the wiring inside the property is "okay".

I've not been using the electrics, so I wont need to replace anything that blows up. It doesnt seem to do anything to A/C stuff like the landlords white goods.

The landlord has paid for two electricians to come round, and they were fairly motivated. But they didn't really pay any attention to the external cupboard as that is YEDL's matter. YEDL are sending somebody else later.

I've already moved my equipment elsewhere, my computer, and it doesn't buzz in other properties.

I've got onto YEDL again as it seems that only Flat 5 and Flat 8 are buzzing from the cupboard and that makes me unsure whether it is interference at all. The YEDL guys paid no attention to the cupboard either, as I have only just discovered that it is buzzing there also.

I'm not ready to give up yet though I have already put it in writing to the landlord that this is unacceptable. Unfortunately, as far as my contract is concerned, the wiring in the apartment itself has been certified therefore I am on uneasy ground. It could get very messy if I decide to move out. I have contacted a solicitor regarding this also.

I am in Beverley, East Ridings of Yorkshire.

Am still working on getting a picture, not had time to do so yet

 

[tim west]

Does the neutral for each meter 5 and 8 both go into a small black box?

Does the neighbour in flat 5 or 8 get home around 5pm?

 

[securespark]

But apparently you can afford to replace anything that gets damaged by this RF storm that you're suffering.

Now, I know the weather's taken a turn for the worse, but it's not fair blaming Rob for it, even if he and the OP live in Yorkshire.

 

[OilLecky]

I read your problem and, like most others, I'm intrigued.
From what I gather the noise is heard by you from the TV (etc) power supply and not the speakers ( there is a subtle difference, reference possible causes). This seems to be confirmed by the fact that the meters for flat 5 & 8 are also buzzing. Is it what is generally called "mains hum"? i.e. is it the same noise that you hear from the bathroom shaver socket if you plug in an electric toothbrush or re-chargeable razor or torch? ( But obviously, in your case, louder.)
A previous suggestion mentioned the metal laminations in such things as transformers making a noise. This is very true and usually when it occurs it gets louder with the amount of (electrical) load being carried.
When the noise re-occurs, try the following.
Switch off the main isolator switch for your flat and go and listen to the two electrical meters. Do they both still make a noise? Does the noise stop? Does the meter belonging to the flat that you do not live in still buzz?
If the noise stops then it is probably a load in your flat that is getting things going. If only the neighbours meter is now buzzing it looks like they may have something that generates the noise.
Also if the meters are of a type where you can see the consumption. i.e. there is a wheel spinning around or numbers are displayed, see if one of them is showing high power consumption. You could even take some readings at 5.o'clock and check again at, say 10 o'clock and see what everyone is using.
If someone is using a lot of power then you will have to be diplomatic and speak to them and ask what it is. Perhaps say that you think there may be a faulty circuit in their flat. (Be careful though, it has been known for police helicopter infra-red cameras to pick up high energy use houses and discover hydroponic farms for exotic plants!!! If the guy has dark glasses and a bulge in the arm pit say, "Sorry wrong flat!" And leg it!)
Another thing that has occurred to me, again on the "transformer" theme is the use of goods made in the USA. Often our US cousins prefer to use equipment they are familiar with (or for US military in the UK, that they can buy on-base at the "PX" hypermarket.) These are usually 110 volt so they use massive transformers to convert our power supply down. Something like this could send electrical noise through the wiring.
The timings do look like some consumer equipment that is in use when someone is at home, like a computer or a TV. Or is someone re-charging something that they use at work during the day? Often a modern pulse width modulated power supply, perhaps for battery charging, can be noisy. (electric wheel chair, electric bicycle etc?)
First though, try to see if "the other flat" is generating the noise as I suggest above. (If you have access to a switch that could isolate the other flat it would be improper for me to suggest that you turned it off to see if the noise stopped.)
Good luck. Please keep us informed of how you get on.

 

[ncoups]

I'm just an apprentice, but from your problem and things people have been suggesting re: neon lights, I recon its a 3rd harmonics issue.
What does the neutral connection on your meter tails look like at DP breaker terminaion?
Where I work there was a similar issue with neon lighting in the bus shelter interfering with surrounding circuits on other phases of supply. The solution was to have more CSA on the neutral tails.
hope this help, if not, no doubt lots of uppity sparks will have a go at me!

 

[Taylortwocities]

Its a good thought. There's more and more problems with harmonics on neutrals through increased computer and accessories being plugged in.

I remember there being a nasty question on this in the 2391 exam a few years ago.
Solution was larger neutral.

 

[st07]

Was there ever a resolution to this?

 

[MEllis1]

Gutted, read all the way through and no solution!