In message ,
Andy Wade wrote:

[re. isolation of a central heating system]

I doubt that the switch on /any/ 13A socket, whether SP or DP, could be
classed as an isolator, due to its not meeting the requirements for "the
position of the contacts to be externally visible or be clearly,
positively and reliably indicated." [476-02-02]


Why not? What does the rocker switch do (a modern one with red splash)
if not "clearly, positively and reliably" indicate the state of the
switch?

These switches are also designed to interrupt the full load current of
the socket, which implies that their contact gaps must be the same as
for SFUs which are usually classed as isolators I think, and are
certainly allowed for isolating central heating systems AIUI.

Hwyl!

M.

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Martin Angove: http://www.tridwr.demon.co.uk/
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