UK Earthing back to neighbours in terrace?

[Mindgirl]

Been asked to do some rewiring, and have said needs upgrade of consumer unit really
Main question is regarding earthing - Zs reads at 0.45 ohms (which suggests at TNS) But cannot see where earth cable goes to from old fuseboard.

There is no earth to fuse carrier or cable to fuse carrier in house.
Im guessing it goes to neighbour, and they actually have a looped supply.
Current cable is not even 10mm - and if earth is back to neighbours incoming supply - I guess I’d need to ask DNO about getting it switched to inside the clients house?

I can’t access neighbour to confirm all this conjecture - but have asked client to talk to them and get me a pic of their incoming supply

 

[bennie]

Been asked to do some rewiring, and have said needs upgrade of consumer unit really
Main question is regarding earthing - Zs reads at 0.45 ohms (which suggests at TNS) But cannot see where earth cable goes to from old fuseboard.

There is no earth to fuse carrier or cable to fuse carrier in house.
Im guessing it goes to neighbour, and they actually have a looped supply.
Current cable is not even 10mm - and if earth is back to neighbours incoming supply - I guess I’d need to ask DNO about getting it switched to inside the clients house?

I can’t access neighbour to confirm all this conjecture - but have asked client to talk to them and get me a pic of their incoming supply

probably a 6mm going to a water or gas pipe. You can always phone network power and ask them, you can also ask them if you can change it to a TNCS.

 

[Mindgirl]

probably a 6mm going to a water or gas pipe. You can always phone network power and ask them, you can also ask them if you can change it to a TNCS.

Thanks - yes have asked if they can change to TNCS - 4-6 week lead time apparently

To sign off the work, I’d need to have visual site of adequate earthing and not just an ok reading - I don’t think Im being too ---- about this am I?

 

[bennie]

Just though I'd say that I didn't mean they'd tell you where the earth went to but that they would be able to tell you what the earthing system is.

 

[bennie]

Thanks - yes have asked if they can change to TNCS - 4-6 week lead time apparently

To sign off the work, I’d need to have visual site of adequate earthing and not just an ok reading - I don’t think Im being too ---- about this am I?

No your right, because you've changed the DB and carried out remedial work you have to be able to confirm that the main earth and the bonding, if its necessary, is up to current regs.

 

[timhoward]

To sign off the work, I’d need to have visual site of adequate earthing and not just an ok reading - I don’t think Im being too ---- about this am I?

I agree, you need to understand the earthing.
I guess there are no other clues, like an up front RCD or the old CU having a main switch RCD?

Also you said Zs, did you mean Ze, testing to the unknown cable while it was disconnected from CPC bar?

 

[MJPD29]

Thanks - yes have asked if they can change to TNCS - 4-6 week lead time apparently

To sign off the work, I’d need to have visual site of adequate earthing and not just an ok reading - I don’t think Im being too ---- about this am I?

No you’re correct in what you’re doing, although I’d expect the provider to be able to answer your question. If you make a case that it’s ‘unsafe’ I’m sure their response will be quicker.

 

[Mindgirl]

Thanks all. Im back there tomorrow, and hopefully be able to trace back earth cable.