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wonder if someone has wired the socket in a cable only capable of 6a and the sockets been used at 13a and melted the cable...
I said that in post #15

But the OP is choosing to ignore the collective wisdom of the forum and refused to believe this circuit is the problem and seems not to want to get an electrician in to look at it.  So I doubt there is much more we can do to help.

 
I said that in post #15

But the OP is choosing to ignore the collective wisdom of the forum and refused to believe this circuit is the problem and seems not to want to get an electrician in to look at it.  So I doubt there is much more we can do to help.

sorry, missed that post

 
Why would that socket/lights  with the so called 'melted wiring' be working perfectly then and not trip out the corresponding breaker?

 
Thanks Andy.  I accept there can be weird symptoms it seems with insulation probs. .  Also on the 9 breaker board, I think I recall some buzzing on that board when trying to use something - indicative of a short there also?  

I don't know if this is universal but I mentioned that there are two RCDs.  The first one which governs the whole board and ONLY these three breakers stays on fine when the socket and lights are being used to full capacity - This RCD doesn't trip.  Neither does the individual breaker governing the socket/lights.

Only the other RCD which governs the 9 breakers trips when this it seems unusual, light/socket is being used to anything above a low setting on a hair drier - basically the same as any of the other sockets on the 9 breaker board currently.  

 
Why would that socket/lights  with the so called 'melted wiring' be working perfectly then and not trip out the corresponding breaker?
You missled us in your first post by saying you could only reset the RCD when that circuit was turned off, so I assumed it had a fault. Are you now saying that is not the case?

If I turn off one particular switch out of the group of three which covers the hall light and socket - then the main on/off switch which covers the 9 switches WILL stay on.
 
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Hi there,

You say the first RCD governs the WHOLE board including the second RCD. This is wrong..... Unless it was installed by a numpty, the board is effectively, two separate ones...

You could have a neutral and earth welded together and set in concrete and no MCB will trip, RCD sure will though..

You have an insulation fault. N/E and you will not even find which circuit it is on [never mind the fault] without the correct equipment. could be any of them.......

You can ponder this all you like, that is the fact of the matter, you need the correct equipment, end of.....

john...

 
Hi there,

You say the first RCD governs the WHOLE board including the second RCD. This is wrong..... Unless it was installed by a numpty, the board is effectively, two separate ones...

You could have a neutral and earth welded together and set in concrete and no MCB will trip, RCD sure will though..

You have an insulation fault. N/E and you will not even find which circuit it is on [never mind the fault] without the correct equipment. could be any of them.......

You can ponder this all you like, that is the fact of the matter, you need the correct equipment, end of.....

john...
Not qualified to say if it was a numpty electrician, no doubt there are plenty around.

However I can confirm this, the first RCD states on it "Main Switch for all circuits" and the second RCD which governs the group of 9 MCBs is somehow interconnected as it trips the MBC on the first circuit governing the light and socket - when there is power running through it greater than a hair dryer on a low heat setting.

I have not 'misled' in my initial post - I am simply figuring this out as I go along and I realised after my first few posts it would be a good idea to try this lone socket on the 'first' circuit with the low setting hair drier  and sure enough, just like the group of 9 MCBs on the 'second' circuit it works with this small amount of charge running through it.

However, just to clarify, when the 'second' circuit of 9 MCBs is completely off, this lone socket in the 'first' circuit of three MCBs behaves normally and holds its normal charge (can run a washing machine/fan heater/full hair drier setting etc. from it).

Just getting to grips with the terminology,  also there is a window of waiting for the Electrician.

 
Hi there,

You say the first RCD governs the WHOLE board including the second RCD. This is wrong..... Unless it was installed by a numpty, the board is effectively, two separate ones...
It was common for a 100mA TD time delay to be fitted as a main switch on TT systems. no idea what system or board off has though

 
It does say Main switch and also is very clearly marked RCD.   The other one just says RCD.  There is no test button on the "Main switch (RCD)" (This is how it is labelled).  There is a little yellow test button but that only governs the group of 9 MCBs.  Not the first circuit of 3 MCBs and is located on the second RCD.  

 
Blimey, this is a confusing thread. I first thought that the OP said "socket" when they meant "circuit", but I am not so sure now.

A picture of the consumer unit would go a long way to explaining it.

 
It was common for a 100mA TD time delay to be fitted as a main switch on TT systems. no idea what system or board off has though
I don't know if this is the answer you require but it is a CU Electrium part no. b4471/2  The main switch (RCD) does say on it 100a 100mA...

Thanks All.

 
Hi Off,

What you think is the first "RCD" is not one then, just a main switch.. Does it have a test button on it??

john..

If it trips itself then it can't be just a switch.

A lot of the tests you are doing are proving or isolating very little, because as has been said MCBs are single pole devices, they do not disconnect the neutral. So a faulty cable connected to an MCB that you have turned off can cause RCD's to trip when any of the circuits sharing the common neutral bar are energised. You need someone with the correct test gear, RCD tester, Insulation resistance tester, earth loop tester. to open up the board properly isolate relevant circuit(s) then test to find the most likely cause of the problem. 

You need to prove the RCDs are operating correctly within spec.

NSB06 sounds like a Wylex MCB, they have had some issues a few years ago inc a product recall, have yours been verified as not from faulty batch.

You need to verify the individual circuits don't have an earth leakage somewhere. IR testing the cables can check their integrity.

You need to verify the integrity of the earthing arrangements, As Andy suggests you may have a TT installation possibly with an earth rod that has poor continuity. 

(electrium are a group that include the brand names Wylex, Crabtree, Volex etc. their CU's normal have one of these brand names on the front)

http://www.electrium.co.uk/products

None of the above can be done by switching things off/on and plugging in  hair-driers. You do need someone to come and get the cover off and do some testing.

Doc H.

 
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I have  a Consumer unit from electrium part no: b4471/2 (I cant find a pic of it on the internet, sorry).

It has the main switch which switches on/off the whole board followed by three switches which are for lights in my home and one socket which work perfectly.

Another on/off switch which covers the further 9 separate switches for various household sockets, cooker etc.

If I turn off one particular switch out of the group of three which covers the hall light and  socket - then the main on/off switch which covers the 9 switches WILL stay on.

I can then use anything in the house so long as it holds a charge of no more than a hair drier on a low setting! If I turn the hair drier up to high - then it trips out.  Again, this is on any socket in the house.

Does anyone have any ideas on what the problem is?

Thanks

Off
I am unclear as to whether the cluster of 3 MCBs and 9 MCBs constitutes the label 'circuits'.  However the confusion seems to have arisen because it appears somewhat unusual for the house lighting MCBs also to contain one socket too...

 
I am unclear as to whether the cluster of 3 MCBs and 9 MCBs constitutes the label 'circuits'.  However the confusion seems to have arisen because it appears somewhat unusual for the house lighting MCBs also to contain one socket too...
The confusion is pretty much irrelevant, see me previous post #35. You need correct testing done to move this issue forward.

Doc H

 
The confusion is pretty much irrelevant, see me previous post #35. You need correct testing done to move this issue forward.

Doc H
Yes, thanks for that post. I do understand that.  However I do have a better idea of what the problem is now.

 I was answering Rob_The_rich who was confused. 

There is a problem DH with every time I post it shows error messages 'warning'  covering the page and it logs me out... I am also unable to quote and multi quote properly.  Maybe it is a ghost in the system following me about :)

Ok.  Sods law.  It didn't do it that time.  Maybe it has fixed itself. 

P.S.   this is my third separate post to you DH but it is sticking it here instead amongst my other post.  I have tried posting in another forum this problem, but it won't let me.    Just mentioning it in passing.

According to this article: http://www.neweysonline.co.uk/News-Electrium-Product-Recahow to ll/Static.raction

I can rule out faulty batch.  Good.   Thanks.

http://www.neweysonline.co.uk/News-Electrium-Product-Recall/Static.raction

Link not working - trying again.

 
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