Earthing for 3 phase boards

[Daveh36]

Hi just after opinions on this one got three 3 phase supplies all 25mm 4 core swa, armour not been used for earth would you run a seperate 16mm earth for each supply or just loop all the earths from 1 16mm all the supplies are right next to each other

 

[littlespark]

Why cant you use the armour?

You've got 3 cables all running to and from the same locations?
If they were all running to different places, i'd say 1 x 16mm each...
It doesn't seem enough... but then 3 sounds like too much.
Go for 2 x 16mm

 

[Daveh36]

it's 3 small boards all.next to each all fed from the same main distribution board just not sure whether I'd get away with the 1 earth going to an earth block and then to each board

 

[Strima]

Yes, what about using the armour?

What does the adiabatic say?

 

[Yozza19]

What’s the 3 boards for rarther than 1 big board

 

[Nigel]

I would def not loop all from one 16mm cpc no.

 

[The Ghost]

If it is just for cpc why not use the armour and fly lead to earth terminal?

 

[Pete999]

If you have correctly sized the main earth for the 3 phase supply to the main board, the surely you should use the same sizing formula for sizing the main earthing conductors to the remaining 3 sub main distribution boards, after all commonsense rules OK.

 

[Chris1234]

Depending on environment I’d use swa for Earth then a separate Earth connected to all three, just in-case.

 

[dmxtothemax]

The most important thing is -
Can it carry the required fault currant !
Thats what size you use !

 

[Wilko]

Hi - a 16mm for each and you probably don't need to look further, but otherwise few questions to help clarify -
Installation means of earthing?
Are sub boards having the same earthing design? Incoming conductor size?
Bonding requirements?