Exporting PME

[chloebear]

I have a project to install 3 new TP distribution boards on a working commercial/industrial site.
The main incoming supply is 3phase PME.
The feed cables out to the new distribution boards will be a maximum of 40metres from the incoming supply and run in Swa cable (some above ground & some below).
The new distribution boards will supply machinery etc in workshop/sheds on site.
Can I keep the earthing system as Pme or do I need to make each of the new distribution boards a TT earthing system?

 

[jeremy]

There's something in the back of my mind, ( could be a fly!), about DNO preferring a seperate bonding conductor when extending the EZ. I could have made that up though.

 

[KennyKen]

I personally would utilise both armouring and seperate CPC. I wouldn't rely solely on the armouring. Especially the gland brands of today which Hardly bite into the steel wire! Belt and braces!!