3.2.4 Functional switching
Functional switching is used in the normal
operation of circuits to switch them on and off. A switch
must be provided for each part of a circuit which may need
to be controlled separately from other parts of the installation.
Such switches are needed for equipment operation, and a
group of circuits can sometimes be under the control of
a single switch unless separate switches are required for
reasons of safety. Semiconductor switches may control the
current without opening the poles of the supply. Fuses and
links must not be used as a method of switching.
A plug and socket may be used as a functional
switching device provided its rating does not exceed 16
A. It will be appreciated that such a device must not be
used for emergency switching (see