Hi Dave

There are no restrictions on the siting of CCUs; barring the obvious of course!!

Are you also moving the meter? This will incur significant expense from your utility provider...

It is possible to buy a metal enclosure and fit a terminal strip ( NOT choc-blocks! ) to join all the cables. A good sparky would be able to do this in a trice. However, it sounds to me as though space is going to be at a premium...

The minimum tails csa is 25mm. Some utility's DO have regs concerning the maximum length of tails to the CCU ( along with their own minimum csa requirements ) you need to check that. Also they may want them in a trunk... Also, check on their requirements for the main earth bond, which for a 100A TN supply is always at least 16mm, with 10mm for the supplementary.

Some thoughts: If you are moving the meter, and you can; put it outside in a service box. You can ( though it sounds radical! ) if this is a cavity wall, blatter out the inner leaf and mount the wooden board on the inside of the outer leaf. I have seen it done - but I can't vouch for the building regs on that bit!

Regarding voltage drop, it is unlikely that your circuits will be running at approaching critical load for the runs as they are. If they are, a way around this is to upsize the 'extension' to take account of this. However, if your loads are this 'tight', you might ask your spark to split some whilst you're on with this job...

Hope that helps a little! [Linked Image]

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