In message ,
"Owain" wrote:

"Martin Angove" wrote
| "Owain" wrote:
| If the boiler is connected by plug and socket it must be an
| unswitched socket. This is to ensure the plug is pulled to
| provide DP isolation.
| Surely it would also be ok to use a DP switched socket then?
| They're pretty universal these days with SP only saving a few
| pennies at the extreme budget end of the market...

The point is that if a switched socket is used, it is not apparent to Mr
Boiler Man whether it is SP or DP. The possiblity remains that Mr B M will
switch off at the socket, thinking it is DP, when in fact it is SP. Using an
unswitched socket ensures the plug will be pulled (or of course an FCU which
are always DP AFAIK)


I'd have thought it more likely the other way around:

Boiler engineer who does this sort of thing for a living will always
unplug the boiler rather than assume the socket is DP switched.

Householder who thinks the internal fuse in the boiler may have blown
and wants to DIY without calling in a boiler man (or other similar
situation) may merely switch the plug off without thinking. A DP plug is
then as safe as a non-switched plug or an FCU.

Hwyl!

M.

--
Martin Angove: http://www.tridwr.demon.co.uk/
Two free issues: http://www.livtech.co.uk/ Living With Technology
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