On Thu, 29 Jan 2004 16:55:54 -0000, "Christian McArdle"
wrote:

It's not wrong, it is the same as running the lives from the rose to
the switch, its just that this method bypasses the rose.

No it isn't. In a loop in system, the power feeds are balanced. The switch
drops are balanced. It is all balanced.

Actually, now I think about it...yes!

If it was to be banned you would have to ban all types of 'unbalanced'
cabling, e.g. singles, 3 phase and anything else that doesnt carry the
same current on the neutral returned as the live feeding it.

Indeed. In a domestic setting, unbalanced cabling is simply not required and
will cause considerable distress and discomfort to hearing aid users.

In what way would 3 phase in one cable not be balanced? (Without tripping
the RCD due to an earth fault). You don't even need a neutral to balance it,
although if a neutral is used as a live conductor, it MUST also be present
in the cable.

If a TP&N supply was feeding a DB that was feeding a mixture of
balanced TP and SP loads the supply cable to the TP DB would be
unbalanced between L1,L2,L3 & N.

Singles, indeed, should be used with caution (i.e. only if T&E is not
available for the cross sectional area) and routed adjacent with the other
cables of the circuit to reduce imbalance. The closer the better, provided
that cable grouping derating allows it.

No-one says the wiring methods adopted are perfect in all situations,
that's why careful selection of the best method for the installation
is required.
In a domestic situation it is highly unlikely to have a induction loop
system fitted.
If you were going on the basis of making all homes 100% disability
friendly you would have to get rid of all stairs, sharp corners,
steps, visible only warnings etc...
I think the term 'reasonable expectations' would apply to all
installations.


SJW
A.C.S. Ltd.