Sizing bonding conductors

[jamie-spark]

Jamie-spark

Not sure the direction you are going here. It must be the man flu I have

I have looked at GN8 although mine is to the 16th Edition dont think it has been amended can see what you are saying.

But think about it the original wiring should have been designed accordingly!!!!! If the sub supply earth is less then the bonding conductor then this would be wrong. The conductors have to be capable of carrying the maximum fault current.

You are going to need to perform calculations and not rely on trying to find a written answer

Just my point it never has been designed to meet the regulations. the sizing of bonding conductors is the same in the 17th as the 16th so your guidance note 8 is still relevant. There is NO CALCULATION for bonding conductors. the only way to size bonding conductors is by use of table 54.8 and by looking at the supply characteristics at the origin of the installation. I think you may be getting confused by calculating earthing conductors by the use of the adiabatic. if you read over GN8 you will see .