6mm incoming earth

[i=p/u]

Has to be a minimum of 10mm due to mpb..

 

[DNO1981]

Tails leaving the meter look 25mm and the earth looks like 10 or 16mm (its no 6mm)

if I were changing the board I would pull back the suppliers earth , put a block next to the head and run my new 16mm and connect both at the block

Thats a good thought

 

[Pretty Mouth]

There is a note in Best Practice Guide 1 (CU changes) that says a 6mm bond on PME can be left in place if it has been there a long time and shows no thermal damage:


3. A 6 mm2 main protective bonding conductor size could be deemed adequate where the minimum size required by Regulation 544.1.1 of BS 7671 is 10 mm2, if the bonding conductors have been in place for a significant time and show no signs of thermal damage

 

[i=p/u]

Yeah he started of saying he had 6mm earthing conductor.... then we jump all over the place.

But a Welsh man wont the darts on diff channel 180v

 

[Dustydazzler]

The ferret

 

[cliffed]

Definitely looks bigger than 6mm…its not usually connected like that,always from the side terminal…

 

[DNO1981]

Definitely looks bigger than 6mm…its not usually connected like that,always from the side terminal…

Definitely a 6mm that's been confirmed funny thing is underneath next to this looks like a chopped earth cable which is much bigger

 

[GBDamo]

Definitely a 6mm that's been confirmed funny thing is underneath next to this looks like a chopped earth cable which is much bigger

Yes, I'm rolling back on this.

Here is a 6mm² in relation to my 25mm² tails and 16mm² main earth.

 

[DNO1981]

Yes, I'm rolling back on this.

Here is a 6mm² in relation to my 25mm² tails and 16mm² main earth.
View attachment 86266

So I guess it wouldn't stop any CU change, they could cut the 6mm earth put in a block then run a 16mm from the CU to the block

 

[Dartlec]

It's the sort of situation that might result in a Catch 22 unless some common sense is applied.

When you go ahead with the fuse upgrade it is entirely possible that the DNO will demand an up to date electrical certificate for the property to show that everything is in place and suitable for 100A, before they do any work. So then you'd end up in a Chicken vs Egg situation.

In most cases (having carefully assessed the situation) I'd personally feel comfortable with doing as suggested, with 16mm earth from the new board to a block near to the main head (and likewise with 25mm tails to henley blocks connecting to the existing 16mm ).

That would be on the understanding that the earth was to be upgraded (or that the DNO would decide they were happy with existing) - as well testing the existing Ze (test of the level of the current earthing) and a quick check with the adiabatic. I'd upgrade main bonding to 10mm too where it was reasonably practicable to do so.