Is this earthing method dangerous?

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I noticed my neighbour's main earthing conductor has been moved from a simple clamp on the incoming cable sheath to the neutral in a Henley block on the cable from the meter to the CU. I know enough to know this is wrong, but is it dangerous? I would rather not say anything to my neighbour because I have found from past experience that some people don't like to be given information that will cost them money to put right. However if it is really dangerous I will have to say something.
 
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I get in trouble for looking at the steel conduit and tray work in supermarkets...if I started looking at my neighbours earthing arrangements every time I popped in for a bowl of sugar I think I'd be up for divorce!
 
That's PME earthing. Nothing wrong with it at all. More info in the wiki.
 
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as long as there is a constant neutral connection, there shouldnt be any issues.

As for earthing through the neutral when there isn't PME in place, It could raise possible issues with the neighbours electrical installation in their property.

Chances are you share the same type of earthing system, call your DNO and ask what type of earth is in place.
 
Well if your neighbour has DIYed a TNS to a TN-C-S, without the knowledge of whether it is safe to have PME arangement on the neutral.
Considering that the supply neutral will need an additional source electrode.
It could be a problem, contact the DNO
 
Thanks to everybody who has tried to help.

Our houses were originally converted to TN-S about 35 years ago by London Electricity using a simple clamp on the incoming cable. (Previously the lead water supply pipe was used.) Is this adequate nowadays or should it be soldered on to the sheath?

I will phone the DNO (a Chinese company called UK Power Networks I think) to find out what is available. I expect I will have to pay for a visit before I get an answer.
 
as long as there is a constant neutral connection, there shouldnt be any issues.

As for earthing through the neutral when there isn't PME in place, It could raise possible issues with the neighbours electrical installation in their property.

Chances are you share the same type of earthing system, call your DNO and ask what type of earth is in place.

I called my DNO who said they did not store this information. If I was worried about my earthing I should call in an electrician. If he finds the earth loop impedance too high then the DNO would come out, free of charge, to try to rectify it, although "it was not [their] responsibility".

It doesn't really help me what to say to my neighbour.
 
It's possible they have spoken to British Gas at some point to ask for PME. I did and was told by the MAST team to "get your electrician to break the seal and put the earth in the neutral box." After further questioning they decided I should contact the DNO and found the number for me to call.
 
It is not allowed to have the neutral and earth connected on the consumer's side of the installation.
 
It depends on what method of earthing it is supposed to be and what may go wrong.

It's just wrong.
 
I called my DNO who said they did not store this information.
I can believe that they won't have records of how the earthing system has been implemented within each property, but what their records will tell them is whether the supply to the property has been "PME'd" (hence suitable to be treated as TN-C-S).

If I was worried about my earthing I should call in an electrician. If he finds the earth loop impedance too high then the DNO would come out, free of charge, to try to rectify it, although "it was not [their] responsibility".
I think they've missed the point. Given that the installation's earth has been connected to the supply neutral (albeit on the wrong side of the meter), the loop impedance will almost certainly be low, but that doesn't alter the fact that your neighbours arrangement is wrong (contrary to the Wiring Regulations, BS 7671), and possibly dangerous. With regard to the question of 'possibly dangerous', a lot depends upon what I mentioned above. If the supply to the property has been PMEd, then the only problem is the 'technicality' of the earth being connected to neutral on the wrong side of the meter - in every other sense it is a conventional TN-C-S/PME system. However, if the supply has not been PMEd, then things are very different - to have TN-C-S without PME is regarded (by the DNO, for a start) as 'dangerous', and unacceptable (probably illegal) in the UK.

If you could find someone at the DNO who knew what they were talking about, they ought to understand the concern. Furthermore, if it did transpire that the supply has not been PMEd and the installation therefore needed to be returned to TN-S, it is really only the DNO who can/should re-attach a connection to their cable sheath (apart from anything else, it could prove a very hazardous exercise, particularly if the supply cable is old).

Kind Regards, John
 
The call centre's know little more than the MPAN in a lot of instances. Usually the best way to get past the call centre is to write to the DNO.

Fill in the form below and state you fancy a PME upgrade like the one your neighbour's got. Describe it and include a photo of yours and the neighbour's earth connections (you can go round & take photos on the pretense of wanting the "upgrade" like they've got).

Once you've had a response you'll at least be in touch with a human being who understands the network (connections engineer) and will then confirm and/or help you further.

http://www.ukpowernetworks.co.uk/internet/en/help-and-advice/documents/SS_APPLICATION_FORM.pdf
 

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