On Mar 9, 5:56*pm, wrote:
Was it really necessary to increase the earth conductor size? It was only
needed in some cases where rewireable fuses were used. It may have been more
economical to have outlawed fusewire, requiring cartridge fuses and MCBs to
be used.

Committee members do not have to declare their commercial
interests :-)

A downside with ring final circuits is where a house is multiple
occupancy renters. It can be better to have 32A ring/radial for
kitchen, then 16/20A radials for each room. Likewise for disabled re
any important equipment.

The 32A ring final is much maligned, but does have many benefits.
- We have plug top fuses, but unfortunately lost arguably better round
pins
- It can serve a larger area, offers two paths to balance loads
although I suspect many unbalanced, two routes for CPC re lower EFLI
(& hence larger area served), more conductor CSA (5mm) than a 32A
radial (4mm) would afford, length not restricted re EFLI (4mm has
oddly 1.5mm CPC, ring has twin 1.5mm CPC).

The cost benefit was in fuseboard ways incidentally, not just ease of
new build installation. It made it cheaper for builders, put simply.