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Installers must assume that, domestic
installations will not be under the supervision
of skilled or instructed users, socket circuits
certainly will be subject to use by the general
public.
However, any circuits wired by traditional
methods (twin and earth cable at a depth of
less than 50mm) without mechanical protection
are required to be afforded ‘Additional
protection’ (a specific requirement of the 17
th
edition) by use of an RCD not exceeding 30mA.
Once it is accepted that all circuits will require
30
mA RCD protection the issue of how this
additional protection is applied should be
considered?
Circuit division within an installation may be
necessary, (ie: downstairs lights and upstairs
sockets may share one RCD, while upstairs
lights and downstairs sockets share another)
to avoid unnecessary loss of light or power,
following the operation of an RCD. It may be
that some items of equipment will require their
own RCD.
All domestic installations will incorporate
socket circuits and bathroom circuits and these
are addressed individually by the 17
th
edition.
Crabtree’s range of consumer units provides
many options to installers as they strive to meet
the new regulations.