PME to Garage

[DrSnooze]

Hi all, Iv'e spent some time reading through old posts to find the correct answer to my question but I'm still a little unsure...
I'm suppling a db into a garage from domestic supply within a cottage. The garage is 3m away from cottage. The cottage supply is pme.
There's a 17th edition split load board in place with spare ways to utilise. I have some 10mm swa 3 core made available to me for nothing so intend to use it even though it's a bit over sized for the load requirements. So pressumebly ... I can install a db in the garage without an additional rcd as it's fed from a rcd protected circuit within the cottage. There is going to be a copper water pipe in the garage fed through a plastic pipe from the cottage but will then continue with copper to a toilet and tap. So do I need to bring a separate bonding conductor from the met ( in the meter box ), or the earth bar in the fuse board?
Alternatively can I use the 3rd core of the swa as a bonding conductor? If so does that need to be kept separate from the earth I take from the swa gland to the garage db ?

 

[Engineer54]

If there is any copper pipework in the garage then yes you will need to bond that pipe back to the MET in the cottage. As your using 10mm SWA cable you can indeed use the 3rd core of your cable, the SWA will then be your CPC.... Nothing needs to be kept separate, you will need to take a flying lead from your SWA cable gland to the DB earth bar (same at the supply end). So both gland/SWA and 3rd core bonding cable will connect at your EMT in the DB. You then need a 10mm cable from the met to bond the copper water pipe.

You may not even need to bond the copper section of water pipe, best test it to find out if it is extraneous, if it's over 22,000 ohms then it won't require bonding...

 

[Knobhead]

If anyone mentions one of those pointy thing that goes in the ground, I’m going to find one and impale myself on it.

 

[DrSnooze]

That completely confirms my doubts, thank you very much!

 

[Engineer54]

That completely confirms my doubts, thank you very much!

Doubts, what doubts ??

 

[DrSnooze]

I've read that bonding conductors must be continuous from met. is there any exception to this? I.e taking them back to earth terminal in db not local to met if earth from met to db is of big enough csa?

 

[GLENNSPARK]

If anyone mentions one of those pointy thing that goes in the ground, I’m going to find one and impale myself on it.

exportpmeexportpmeexportpmeexportpmeexportpmeexportpmeexportpme......

 

[Engineer54]

I've read that bonding conductors must be continuous from met. is there any exception to this? I.e taking them back to earth terminal in db not local to met if earth from met to db is of big enough csa?

Perfectly acceptable where there is an EMT, the bonding cable can then be routed via the EMT back to the MET .... Your 10mm bonding cable from the MET to the EMT is of sufficient size, the bonding cable from copper pipe (if required) to EMT will also need to be 10mm....

 

[GLENNSPARK]

she sells PME shells.......on the seashore.....

 

[Knobhead]

Your pushing your luck pal
View attachment 9634

 

[Silly Sausage]

If anyone mentions one of those pointy thing that goes in the ground, I’m going to find one and impale myself on it.

Careful make threats like that, you'll do yourself an injure around here.

 

[DrSnooze]

Cheers.

 

[telectrix]

why feed from a RCD in the cottage? better to use a non-RCD way and fit RCD in garage, that way, a fault in the garage won't take out circuits in the cottage.

 

[DrSnooze]

the whole board is covered by 2 split rcds