Extraneous Parts Earth sizing

[Neon Vagabond]

so what about, i take the tncs supply from the garage (2.5mm 3 core armour). This would supply earth to all of the circuits only. And then seperatley i connect a 10mm earth onto the greenhouse frame and then into a earth rod?

 

[Wilko]

No good I'm afraid.
By earthing the frame with a local rod you ensure it is an extraneous conductive part and so needs connection back to main earth terminal. Or TT'ing. See @davesparks post #19 .

 

[Neon Vagabond]

basically im trying to get out of digging a trench back to the house (many reasons).

But my other problem is that inexperienced with "tt ing" something.
So im just supposed to run a live neutral from the garage (unearthed) to the greenhouse, then stick a 30ma board/earth rod.

or do i earth the armour at the garage side but leave the greenhouse side unconnected to its respective earth terminal.

 

[telectrix]

or do i earth the armour at the garage side but leave the greenhouse side unconnected to its respective earth terminal.

yes. earth armoured at supply end. TT the greenhouse. bond the metal frame if required.

 

[Neon Vagabond]

or do i earth the armour at the garage side but leave the greenhouse side unconnected to its respective earth terminal.

yes. earth armoured at supply end. TT the greenhouse. bond the metal frame if required.

top man, cheers