In article .com,
"crb" writes:
Just prior to Part P becoming active, I updated my 1960s fuse box to a
split-load MCB consumer unit.
I was happy that the existing wiring was still serviceable, so decided
to simply route it to the new consumer unit, and then add additional
cabling as required for new circuits.
However, due to length restrictions on the original cables (including
the meter tails), it was not possible to get all of them to reach to
the appropriate positions in the new consumer unit. I did not want to
splice on additional lengths (at least not for 6mm and larger cables),
so the fix I adopted was to re-arrange the layout of the consumer box
such that the Incomer was to the right of the split-load RCD. In other
words, looking at the face of the consumer unit, the split load RCD is
on the left hand side, and the Incomer is approximately in the middle.
I obviously also re-arranged and re-connected all the
manufacturer-supplied interconnecting cables within the consumer box to
suit.
A friend I mentioned this to recently said that he thought it was
unnacceptable, as it was a "non standard" configuration. That led me
to check again in BS 7671 (16th Edition) and I can see nothing in there
that prohibits my layout. Any views?

Providing you are not misusing any of the CU components and the
labelling is clear, there's no problem.

--
Andrew Gabriel