After some advise please- Tn-s earth arrangement

Jimmer84 · Nov 5, 2018

Evening all,

Just after some info on the photo attached. It’s a tn-s system with an Earth going to the cu met from under the floor boards. After lifting the boards I found the earth attached as so... I was expecting to see a clamp around the supply cable, not a choc block with legs of unknown origin attached. Can anyone enlighten me on what’s going on here? Thanks

[ElectriciansForums.net] After some advise please- Tn-s earth arrangement

SparkyChick · Nov 5, 2018

That looks suspiciously like a copper pipe... gas or water maybe, so my guess from afar would be that's bonding not the main earth.

SparkyChick · Nov 5, 2018

p.s. I'm using the term bonding loosely... about as loose at the connection to the pipe

Pete999 · Nov 5, 2018

Roy Rogers has visited the House?

Deleted member 26818 · Nov 5, 2018

There do seem to be a number of bare conductors floating about under the floor boards.
At first glance, I thought split concentric.
I think you need to find out just how many conductors are there, and where they come from.

Octopus · Nov 5, 2018

That’s not pretty.

What’s the Ze like?

oracle · Nov 5, 2018

Earthing and Bonding (to the CCU) must be continuous throughout its length. No joints or connections.

Octopus · Nov 5, 2018

oracle said:
Earthing and Bonding (to the CCU) must be continuous throughout its length. No joints or connections.

Wrong.

oracle · Nov 5, 2018

Murdoch said:
Wrong.

There is no specific statement in BS 7671. It's very clear in GN8 and is something the NICEIC assessor has specifically looked for on previous inspections.

buzzlightyear · Nov 5, 2018

Pete999 said:
Roy Rogers has visited the House

and trigger .and well in to the sun shine .

Octopus · Nov 5, 2018

oracle said:
There is no specific statement in BS 7671. It's very clear in GN8 and is something the NICEIC assessor has specifically looked for on previous inspections.

Ignore guidance notes - that's all they are and many people don't have them

The NICEIC assessor (as usual) doesn't know what he's talking about.

If its not in the BYB or BBB, an assessor can't pull you up on it.

Simples

Deleted member 9648 · Nov 5, 2018

oracle said:
Earthing and Bonding (to the CCU) must be continuous throughout its length. No joints or connections.

That would mean an MET remote from the CU would not comply.

Wilko · Nov 5, 2018

To me that pic does not show the installation earthing type, if that was your question. It looks like a bunch of prehistoric bare cpc bunched together and taken off to MET (?).

oracle · Nov 5, 2018

Murdoch said:
Ignore guidance notes - that's all they are and many people don't have them

The NICEIC assessor (as usual) doesn't know what he's talking about.

If its not in the BYB or BBB, an assessor can't pull you up on it.

Simples

Guidance notes are written by the EIT to help you interpret the Regs correctly and the fact that people do a Regs course, usually at a college that simply prepares you to pass, doesn't mean that you are not responsible for studying it further.

How would you have managed 2391,2,4,5 or 6 without GN 3? Do you ever read it or quote it here, or just use the OSG like any domestic install, r?

Just because people can't be asked to study doesn't mean they can substitute opinion for fact.