Backfed Earth on TT system

[R G]

Hi lads,
Here's a good un .
Went to a job this morning and lady has trouble with a steamer in the workshop . Got there and steamer is faulty causing RCD to trip in workshop and also voltage trip in house at same time , (garage unit RCD main switch), with an earth stake outside workshop 40 meters away from the house , I confirmed the faulty steamer, then took a look at the wiring , at the house and it's TT system but no main cpc to earth rod , only the cpc to all the circuits and no bonding either, took a look at the kitchen and found some bonding in place under the kitchen sink this went outside and under the paving , under the plinth off the kitchen units the bonding goes up in the wall towards a socket , took the socket down and there's the main bonding straight into the earth terminal , so it looks as if the bonding goes to an earth stake , (possibly) then back to this socket and the kitchen ring circuit supplies the earthing for the consumer unit . Zs at that socket was 141ohms further round the house on the lighting 144ohms . Lady says kitchen was refurbed 18 months ago , I can only assume the kitchen fitters did this and that there was no main earth before this , lady has no certs regarding the wiring in the kitchen , anyway the good point I have got to go back and do a full test and Quotation.

 

[ackbarthestar]

Got there and steamer is faulty causing RCD to trip in workshop and also voltage trip in house at same time

I'd be interested to know what the earthing configuration is at the VOELB if the electrode is connected to the MET via the RFC.

- - - Updated - - -

Got there and steamer is faulty causing RCD to trip in workshop and also voltage trip in house at same time

I'd be interested to know what the earthing configuration is at the VOELB if the electrode is connected to the MET via the RFC.

 

[R G]

It's a bit of a mess at the DB at the house really , The VOELB cpc is connected straight to the earth terminal in the consumer unit and as I say there are no other earth wires apart from the circuits themselves , so its relying on the earthing from the kitchen ring circuit and the Bonding and possibly an earth stake , 2 x 10mm earth wires go under the paving , so it looks like it's looped throgh an earth stake .

 

[GLENNSPARK]

it may be that bonding was the main earthing...and `kevin kitchen installer` has been along arsin about with the ring ...
the voltage trip will be a fail....
dont forget though it will work perfectly well as a DP iso in series with the tails....
it will be able to switch load as it was designed to clear fault and as such will have arc shutes....

 

[R G]

As I say the bonding wire goes from the water only at the kitchen sink then on to the earth stake and back to the socket , so it looks like it loops from the earth stake , Regardless really as whole area is now PME and what's required is oil and water service bonding back to MET, contact DNO for conversion to PME , but in the meantime a full test and quotation , the workshop is much more modern but is in a right state including stables and outbuildings also , as you say the Kitchen butchers have done their bit

 

[Knobhead]

Go way, find out how a VOELCB works.

Come back and tell us what you found. After doing some testing.

 

[GLENNSPARK]

As I say the bonding wire goes from the water only at the kitchen sink then on to the earth stake and back to the socket , so it looks like it loops from the earth stake , Regardless really as whole area is now PME and what's required is oil and water service bonding back to MET, contact DNO for conversion to PME , but in the meantime a full test and quotation , the workshop is much more modern but is in a right state including stables and outbuildings also , as you say the Kitchen butchers have done their bit

this is rubbish...
how you going to do your live tests?...

 

[stuartcourt]

with magic

 

[GLENNSPARK]

with magic

sprinkle some Zs dust over it all...

 

[Engineer54]

Someones totally out of they' re depth here. And a i can see a whole set of other problems if and when a PME connection is provided by the DNO!! lol!!

 

[R G]

I Will be going back on Tuesday , I had only spent a short time a the property , I put this on here for advice and I would have given over more info after the next visit , but all I got was a load of crap , Well if that's how you treat people then leave me out , forget anything I have ever mentioned , Mods or Owners of this forum remove me and delete my entries .

 

[Clive P]

Hi,
I don't see the problem with Rays post, he's put all the information forward that he has found on his initial visit. He is going to contact DNO ref the PME connection. I assume he will carry out all the dead tests and verify as best he can the soundness of the installation and give the correct advice to the customer as to what the next steps should be. Or am I missing something?

Regards.