On Mon, 01 Apr 2013 18:04:08 +0100, newshound wrote:

Turn off power, remove socket and separate out the wires.
Turn power on, check out which wires are live, they are the ring the
other (dead one) is the spur.

So only Dave Liquorice and myself wants to do the job properly and
work on a dead supply:-)?

Easy and safer to do than a live test.

Don't always agree with Harry; OP may not have a tone generator but
probably has a volt stick, meter, or horror neon screwdriver.

Why would one want a tone generator? A continuity meter (a normal
facility on any multimeter) is all that is required.

If done with a bit of care, the check described above is pretty quick,
safe, and reliable.

FS (low) VO "safe". These wires are in a cupboard under the sink. I'm not
averse to live working but it does make me nervous, very nervous when
there is more than one exposed live conductor. It's easy to keep out of
the way of one, keeping out of the way of two in a confined space is a
different kettle of fish. I really don't like the FLASH BANG and being
splattered with molten copper... Or getting a belt and in both cases
whacking ones head against the cupboard frame or WHY.

--
Cheers
Dave.