Earthing a second consumer unit

[dave21478]

So....The feed from the meter and main switch goes to the main consumer unit in a house. There is a barn out back that needs powered up, so I have fitted a wee consumer unit in the barn and ran a heavy three core back to the house where I have connected it in parallel to the original consumer unit.

Cable length is about 20 meters.

Should the barn unit have its own earth spike? I thought there would be no harm in having one and have the necessary, but it turns out the barn is built on bedrock and knocking a spike into the ground aint going to happen. At best I could give it a horizontal shallow burial, but only a few centimeters down, so not great.

TBH, I dont see any problem in not fitting one and using the earthing of the original unit. Any thoughts?

[Chancer]

You should in theory run all the earths from the tableau divisionnaires back to the repartiteur de terre  (probably wrong word) at the earth piquet or to the barrette de terre in the main tableau which it sounds like you have done.

That said my pied à terre in the UK is powered by a 2 core SWA cable so I have a seperate earth spike, in France all the apartments are correctly connected to the new main piquet, my own apartment plus the laundry and garage is still connected to the previous one which was checked by Consuel, the tableau in the workshop has yet another but it will soon be removed as it will be converted to the final apartment.

 

so to me, what you have done is fine.

[Gluestick]

I'm with Chance on this, adding a Tableau de Chantiere, or small tableau is simply another sub-system.

Caveat: all provided your "Heavy Three Core" cable enjoys an earth feed which is sufficiently large to accord to the normes. The size of which at present, I simply cannot recall!

It's been a heavy ol' day!

[8-)]

[dave21478]

Yes, I dont see why it wouldnt be ok.

The cable I ran is 3x 10mm, which is massive overkill for a dozen sockets and some striplights, but allows future upgrades if they desire.

The original consumer unit has an earth braid of unknown but large size, the proper uncoupler/test point or whatever its called and the spike is driven deep into permanantly damp ground.

I am not particularly fussed about the normes given the horrific state of the wiring in the rest of the place....and thats "up to standard" and done by "professionals". What I have installed is a hell of a lot safer than the rest of it by a large order of magnitutde.