Seperate / Integral earth CPC on 400A supply

[Ian1981]

Is 0.06 ohms the max zs?
Did 300mm give you an R1+R2 of 0.04 ohms?

 

[Dave OCD]

They don't make anything easier for us as time goes by that's for sure !

 

[Leyland30]

Wow - that was almost helpful. Trimble have outdone themselves.

 

[Leyland30]

Could you post the cable calc for the two options. IMO an external Cpc would be electrically preferential but I guess the brains at IET think otherwise.

 

[westward10]

I think there is a bit of confusion here, the thing I was trying to highlight was that the software said it was ok to use a 5c cable with an integral earth conductor, but not ok to use a 4c cable with a supplementary earth of the same size.

I have been thinking about this and and the only thing that comes to mind is the programme assuming the cpc will pass through a separate hole to the line conductors which would not happen if it were a core of the cable which may under fault conditions be problematic, maybe.