High earth reading

[Inderpal]

Hi everyone


I need some advice

So my meter was making a arching noise and I called out UK power network . Engineer said I have a very old dial meter which needs changing .

When he done his tests he said my earth reading was high 2.35 but they can't do anything about it as I have a Tenby Clip system which is no longer approved

So my energy provider has put in a new meter but said they can't do anything about the earth reading

I had a electrician come out he said it's UK power network responsibility to fix the high earth reading from the meter ???

Any advice

 

[flameport]

Energy supplier can replace the meter but nothing else.
Only UKPN are supposed to make alterations to the incoming supply.
'tenby clip' or more probably BS951 clamps were permitted for metal sheathed cables several decades ago, and now are not.

In theory UKPN should provide a new earth connection with a CF spring, however they have declined to do that, and then there is the question of whether the problem is actually at that location or is due to some other fault further away in the network.

 

[ericmark]

Interesting question, as far as I am aware the DNO do not need to supply an earth, having a TT earth system is still permitted, but it is the DNO who should tell you what earthing system you need to have. This was required as having a row of terrace houses with some TT and some TN could cause a danger, the same applies in a metal framed building, which may have multi supplies into the same building, but there properties have some distance between them, it is not so important that they all have the same system, but the selection of type of earthing system is above my pay grade, I would need to very carefully decide how to earth a property and in the main only time as electricians that we get involved is when wiring out buildings. Otherwise we do as we are told.

With RCD protection on all circuits 2.35 Ω is not really dangerous, but it does raise questions. In the main with a 100 amp supply with a TN-C-S supply looking at 0.35 Ω or better, and with a TN-S supply 0.8 Ω or better, with a TT supply over 200 Ω is considered as unstable.

@flameport makes a good point,

there is the question of whether the problem is actually at that location or is due to some other fault further away in the network.

the worry is loss of PEN, but since the supplier has been made aware I can't see them allowing that to happen. It is a health and safety issue so has to be in writing, would be interested to see what has been said, as if I was involved I would be considering the watch my back and fax, email, text or what ever method was used would make interesting reading.

 

[securespark]

The DNOs have a duty to maintain an existing earth connection, but not to provide one where none exists.

Although IME, they were very helpful and always obliged, unless there was a safety reason not to.

Edited for grammar.

 

[Ragnar_AT]

Having a mix of TT and TN won‘t work properly if the houses have a shared metal water or gas supply because then the TT earth will be connected to the PEN via the bonding and pipes.

 

[JohnW2]

Having a mix of TT and TN won‘t work properly if the houses have a shared metal water or gas supply because then the TT earth will be connected to the PEN via the bonding and pipes.

As I often report, that's the situation I'm in. I have a theoretically TT installation, but with a Ze of around 0.25Ω, seemingly thanks to a metal water pipe which is bonded in both my and my neighbour's (TN-C-S) houses.