Yet another shed supply

[Timbo_1975]

Yes one more time! Cue rolling of eyes and yawning...

House is PME. 17th Ed dual RCD CU.

Two sheds: first one is 30m from house and requires only light and acouple of sockets.

Second and new shed is where it'll all happen and is a further 30m from the first shed. Customer will likely have ~4kw of PV on it, electric doors, heating boiler & small workshop etc here.

Plan:
o supply from the house CU via a non-rcd 32A MCB initially via 10mm SWA to the first shed CU. Main switch, 2 RCBO's, 1 MCB:
o from here via 32A mcb in 6mm swa to 2nd shed 5 way CU. Switch + RCBO's as required.

Q: does the palnel suggest exporting the earth from house entirely, or applying an earth rod at shed1 or shed2 and bonding armour to suit ?

I am favouring bonding the 10mm swa armour at house end, then applying an earth rod at shed1 to cover everything downstream of here but would like the panels opinion

 

[Deleted member 9648]

Depends on extraneous conductive parts in the sheds...if there are,(and it sounds like there will be in the furthest shed)..and you intend using the PME.(always the best option)..your CPC will have to be sized to double as a main bonding conductor,as main bonding in the sheds will have to go back to the MET and be sized according to the requirements where PME applies,(minimum 10mm)...either that or a separate main bonding conductor will have to be run alongside the SWA.....If all that is hassle TT it as a last resort.

 

[Timbo_1975]

I should have said that shed2 is brand new and is a steel portal frame type.

 

[Deleted member 9648]

Either bond it back to the MET and use the PME...(a good earth)... or TT it(a rubbish earth).. and bond it to the local CU...the choice is yours.

 

[Knobhead]

I can’t understand why your reducing from 10 to 6mm if the furthest shed is going to have a reasonable load.
PS use three core and take a decent earth out there.