Main Earth Size

[eckersecker]

If a distribution board has 16mm tails according to On site guide table 4.4 the earth size should be 16mm. If I have aboard with 10mm earth does this mean C2. In "examples of classification codes " it states '...Cross sectional area does not satisfy adiabatic equation.....' Code 2.
However when I calculate using adiabatic eq. (I could be getting it wrong) I get 5mm.

 

[Geoffsd]

What is the earthing method?

 

[Octopus]

If you have 16mm tails then a 10mm earth will do.

 

[eckersecker]

Earthing method TNCS

 

[Richard Burns]

For TNCS then your earthing conductor needs to also meet the bonding conductor requirements, which 10mm does.
The OSG is just giving you the selection values rather than calculated values.