Advice on an Upgrade

[South Spark]

I'm installing the AC circuit for a solar inverter - not a difficult job usually. On this occasion the inverter is going to be mounted outside (It's IP rated 65) so it's got to be notified as special location.

My question is how far do I have to go in ensuring that the rest of the installation conforms to 17th Edition?

The existing meter tails seem to be 10mm (the tails from the supply head to the meter are 16mm) - I could upgrade these if necessary.

The earth bonding is in 4mm - but the householder does not want me to disturb the fabric of the house.

Could I just note all of this on a cert and put my 16A breaker onto the existing consumer unit?

 

[Superspark23]

My old company used to do this. put an 6mm or 10mm from the top of the main switch of the fuse board and feed a 2nd consumer unit. This could be in a loft so obviously the 6mm or 10mm doesn't has any protection his argument was it was protected from the other end. I totally disagreed with this fort my agument and lost basicly cos he knew best. He was basicly saying he wern't touching anything else of the installation so he was fine. This was proberly no help to you.

But what i would sugest mounting a new fusebox next to the existing one and use an henry block to split the tails