What size earth on a TT ?

[Engineer54]

Forgetting about the min CSA of buried earthing conductors in BS 7671, Would anyone here ever contemplate using a 2.5mm conductor on an earth electrode system that has an Ra value of say 1 ohm or less??

 

[davesparks]

Forgetting about the min CSA of buried earthing conductors in BS 7671, Would anyone here ever contemplate using a 2.5mm conductor on an earth electrode system that has an Ra value of say 1 ohm or less??

I'm sure we could find someone here who would consider it!

 

[123]

Forgetting about the min CSA of buried earthing conductors in BS 7671, Would anyone here ever contemplate using a 2.5mm conductor on an earth electrode system that has an Ra value of say 1 ohm or less??

I'm sure we could find someone here who would consider it!

I doubt that anyone using 2.5mm to the electrode will have an Ra of anywhere near 1 Ohm, 1k Ohm perhaps!

 

[Engineer54]

I doubt that anyone using 2.5mm to the electrode will have an Ra of anywhere near 1 Ohm, 1k Ohm perhaps!

Don't you believe it, there are far too many out there that don't have a scooby doo when it comes to creating a TT system. Most just follow BS7671 and it's accompanying picture book still having this magical numpty 200 ohm figure somehow implanted in their brain...