On Sat, 19 Dec 2015 07:16:44 +0000, Tim Watts wrote:

Yeah - I'll get a new switch of the same make (for same terminal
layout) next time I'm up TLC in a week or two.

Hum, a plain switch running hot when the associated MCB/RCBO is
cold.
Bear in mind that MCBs have a thermal part...I think I'd be down
the
shops tommorow or not use what ever it is until the switch has
been
replaced.

Well, even I'm not going to panic quite that much This is only used
when people are around.

But you still did when your mate came round and commented. B-)

Why is terminal layout so critical?

There's not much slack...

OK 10 mm2 isn't the most bendy stuff but the switch will be on a
47 mm
deep box won't it to give room.

Tricky I know to leave slack with heavy cables, shallow boxes don't
help.

--
Cheers
Dave.