Lights flickering - Significant Problem

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I would appreciate some thoughts on an electrical problem I have.

About a week ago we started to notice lights flickering in the house, these lights were on a lighting circuit and also those on a ring main circuit. The lights would flicker for 3 or 4 seconds, maybe once every 3 hours. Over the last week the situation has worsen and is now causing lights and electrical appliances to go off for a split second (indicating a significant and temporary reduction in the supply voltage).

I have tried to isolate the problem, with limited success, but I am able to conclude the following. If I plug any mains adaptor from a computer into any 13 Amp plug and then switch the 13 amp socket power on, the lights will significantly go off and on for 3 or 4 seconds, this will happen on all of the different ring main circuits in the house. And I can repeat this occurrence with a fair degree of consistency.

I would add that no overload breakers will trip as a result of excessive current or any of the earth leakage trips will operate.

What I am unable to get my head around, is how can the voltage significantly drop when no earth leakage or breakers actually trip? Any why does a low power device, such as the power adaptor, cause the voltage to drop?

I have had the electricity supply to the house checked and that’s OK.

I have attached a photo of the fuse board just in case that helps (The main isolator is on the bottom left and this then feeds the bottom buzz bar and a earth leakage trip in the middle left of the picture) . You will notice that a number of breakers are off as we just keeping essential equipment on (internet, fridge, etc).
 

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you have a loose, high-resistance connection, and as it overheats, it is burning away and getting worse.

If you can work out whether the fault affects all the rows in your distribution board, or only one, you will know if it it that row or the main switch.

You could try tightening the screws in the main switches but they will be live even when turned off, so you would be better to get a competent electrician to do it. An insulated screwdriver and other precautions are needed. The overheated cable ends and/or switch may have been damaged and need to be replaced (tightening will not work for long).

I would look first at the more recent additions to your board (brown and blue) as they are considerably less tidy than the original work.

Are you in a farm building? Or industrial premises? Or an unusually large house? You need an electrician with industrial experience, not just a "Domestic Installer" which is the lowest grade of qualification.
 
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Hi
I have checked all the screws in the board and all are tight.
The house is fairly large.
The fault seems to affect all 13 amp circuits.
Would a NICEIC Registered Electrician be OK?
 
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yes, though personal recommendation would also be a help to select between them.

The "Approval" column in "find a contractor" shows what they can do
http://www.niceic.com/find-a-contractor/find-contractors

It doesn't seem to show how long they have been in business. Obviously you don't want a beginner.

p.s.

If you standing by it, you might hear a crackle or even see a puff of smoke.

It could becoming from the meter, incomer or a connection block, if any, or the pole transformer if you have a rural supply.
 
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As John d above and also we had exactly this, from when we moved in, plus random flickering. Eventually things were going off and on rather than flickering so we called the electricity company. When they turned up to look they said they noticed some other of their guys down the road tracing a fault, apparently they could feel the cable exploding a standing on the pavement.
Some furious digging with a mini digger and we were connected via the other end of the road.
So go and ask your neighbours too - although ours didn't notice until it was really bad, so perhaps it depends what phase you're on.
 
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The electricity distribution company has checked the supply from the overhead poles to the smart meter and all was OK.
If you mean they checked for loose/binding connections and remade as appropriate, then you need to do the same for those after the meter.
I'd be tempted to set up a temporary supply from the tails and prove an issue there, then you can show evidence to the electricity company, or otherwise, but that would need a qualified electrician really.
 
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Just going back over my original post and stating what happens:

If I plug any mains adaptor from a computer into any 13 Amp plug and then switch the 13 amp socket power on, ALL the lights in the house will significantly go off and on for 3 or 4 seconds, this will ALSO happen on all of the different ring main circuits in the house. And I can repeat this occurrence with a fair degree of consistency.

Also turning on a light on the ceiling lighting circuit will cause the appliances to flicker as well as the lights.
 
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Safety issue, be aware that on the middle bus-bar (not buzz bar) there are two exposed live parts either side of the group of three 32A? MCBs. Also, on the RHS there is a connection point for a breaker but no DIN rail for it to fix to.

As the fault affects more than two sub circuits this would point to a fault in the main wiring. In your case, smart meter - does it have a dodgy contactor or loose connection? main breaker internal problem or its connections, main bus-bar connection. There is no such thing as simultaneous electrical faults only consequential faults.
 
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Yes, not relevant to the original problem also, but while we're at it those bell transformer output wires don't look adequately insulated, they should be rated for 230v at least while they're within the enclosure.
And the newer rcbos are not matching the rest, although that's a very nitpick.
 
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As the fault affects more than two sub circuits this would point to a fault in the main wiring. In your case, smart meter - does it have a dodgy contactor or loose connection? main breaker internal problem or its connections, main bus-bar connection. There is no such thing as simultaneous electrical faults only consequential faults.

The smart meter and feed has been checed by the distribution company. Could you expland please on simultaneous electrical faults only consequential faults?
 
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