Dual supplies advice

[Griffin]

All,

Would appreciate advice on the following as never come across this before;

Customer has a field opposite his bungalow across a small country lane. In the field is the pole mounted tranny.
There are 2 supplies -Supply 1 feeds a shed in the field (TT) (ex horticultural premisis) also a small ground mount PV array feeds into this
Supply 2 is the bungalow (PME- approx 50m away from pole)

The customer wants to move their domestic supply and meter so they can benefit from the power they generate and not just feed it back to the grid.

The DNO has said that the existing 16mm concentric cable should not be reused as a submain as it is not armoured (it is ducted) and it has no earth.

Question: The customer has asked if the old supply cable can be reused as sub main Install switch fuse/time delayed RCD at supply end then install a rod at the bungalow (domestic circuits are 30ma rcd protected)

Reg 543.4.1 says PEN shall not be used unless.........

He is trying avoid cost of trenching in a new cable / digging up the road, and I would like to quote specific regulations if it is not possible to reuse cable.

Any advice / questions welcome

G

 

[Engineer54]

Question: The customer has asked if the old supply cable can be reused as sub main Install switch fuse/time delayed RCD at supply end then install a rod at the bungalow (domestic circuits are 30ma rcd protected)

Only a complete idiot would sacrifice a working TN earthed supply in favour for a TT roded earth. Don't do it!!!

If the concentric cable is in it's own duct, there is no reason why a concentric cable can't be used. Though it is only a 16mm cable, generally the DNO provide 35mm concentric, as most DNO cables tend to have aluminium conductors, though i'm not too sure about the concentric cables they use.