Outbuilding and shed installation

Hi thanks once again, I am happy and understand how to do undertake the work. But before I begin though I like to know exactly what I am doing in my mind.

And the only thing that Im unhappy with is the earthing arrangements.

I will come off the RCD side then, suprised the incorrcet RCD is on the other side, about £80 to get the right one, I will replace that later.

So connect earth to my c/u, and you say I should use one of the swa wires as an earth also as well as the armour?

So instead of buying a 'gargae' unit, would these items put together be correct for my c/u's in each building?





You mentioned pme when taking about the correct earthing for this system. Now thats eliminated, how do i earth correctly?

Thats all I need to know now,

how to earth my house c/u
how to earth each outbuilding c/u

Comms do you have a paypal account, once I get this sorted, you deserve a donation for all your good work?????

Thanks so much, Simon

email me if you wish [email protected]
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Yes all the items listed will do fine for the outbuildings.

how to earth my house c/u
You will have a green/yellow cable from the cu earth bar down to a rod located outside.
From this cu take your twin & earth (T/E) that will be connected to the swa & connect the live (phase) to the mcb on rcd side / neutral to rcd side neutral bar & connect the earth (cpc) to the earth bar.
Inside your adaptable box join T/E cpc to the swa conductor & armour (I use ring terminals on all 3 & connect via the screw on the nut in the link I posted earlier). Joint the phase/phase & neutral/neutral conductors & run swa to outbuildings.

how to earth each outbuilding c/u

Terminate swa into insulated adaptable box or cu, phase & neutral to mainswitch.
The earth of swa and armour join together (use ring terminal on earth core & join to armour via the screw on the nut I linked in post earlier).
Install a 10mm green/yellow cable from cu earth bar down to a rod driven into ground outside building.

Do the same at other outbuilding.
This is somuch more difficult than actually having hands on to explain if you know what I mean :confused:

I've got a submain on a TT system to do this weekend so if I remember I'll take pics & post or mail you photos.

Comms do you have a paypal account, once I get this sorted, you deserve a donation for all your good work?????

No & dont worry about it, I like others here try to help & give advise because some people like you do seem to want to get it done right & safely (unlike another post I've replied to on this forum today) & I hope you'll stand by your word & have it tested / inspected & certificated.
I cant thank you enough.

Some pics would be great. I am also going to take some pics as I undertake this job and knock a web page up, so it may help others.

I will keep checking to see if you have had time to do the pics.

I have been doing the install over the last few days and its been going really well, I will take some pics later if I can find my camera!!!

Just to clarify an earth question

I have used the armour and one of the cores in the swa as earth and they are connected to each other throughout the install.

Am I right in thinking at both garage c/u's, I connect this earth to the earth bar, then I run my 10mm earth to my earth rods?

ie. Terminate swa into c/u, connect swa core and armour together, then run that to the earth bar. Then another wire down to the earth rod??
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No. One core and the armour are earthed at the supply end. Only the core u are using fior earth is connected at the far end.

The armour is earthed to ensure that the supply fuse trips if the cable gets damaged. The inner core provides the cpc
Ok, so I have two outbuildings.

1st outbuilding swa from house c/u terminates into a box, so does the swa that runs to the 2nd outbuilding, they are connected together in this box. T&E then supplies the consumer unit in the first outbuilding which has an earth rod connected to it.

At this box, do I just use the core in the swa as an earth. And join the swa armour that runs to the 2nd outbuilding with the swa that enters the 1st outbuilding for continuity?

And at the 2nd outbuilding just connect the swa core onto the c/u earth block and run another earth rod (already installed). And just leave the swa armour connected to nothing, just terminated?
Well I completed the job today. All works a treat.

I took it slowly, double checking everything I did and Im so pleased.

The hardest bit was terminating the SWA, and that was only the case as my snips are crap. After doing one, it was fairy easy doing the others.

Thank you to comms as I would not of been able to undertake this without your advice. I will get the work checked by a sparks shortly.

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