"Mike Armstrong" wrote
| It's all surface mounted. Would a plastic box will be OK?
| I've never heared of eddy currents ... what are they?

If you have the phase and neutral of a pair going through different holes in
a metal box, the box in effect becomes a coil round the conductor, and a
current can be induced.

| Do you think that 2.5mm2 T&E cores would be OK for the tails and
| connection to the CU or would 4mm2 be better?

Given that this is a ring circuit with a 32A MCB then the conductors must be
rated accordingly. A *ring* of 2.5mm is (usually) adequate, but for a radial
(which is what the tails between the CU and the submeter are) you should
probably use 6mm.

Bear in mind that as this is an installation specifically for work purposes,
the Electricity at Work Regulations will probably apply. You (or your boss)
would therefore need to obtain inspection and test certificate on the
circuit(s).

Owain