Re: Ring main question

["Paul Helliwell" <g0kao@xxxxxxx>]

Robert

Glad to help. Yes there probably will be one you forget but at least if
you find that when you do take measurements you may notice an odd reading
and that will indicate that something still connected. If you measure
resistance between Live and Neutral on the circuit you are testing you
should not see any low resistance reading on your meter as this will
indicate something connected between the two. If there is nothing connected
and meter on highest resistance scale you should ideally see open circuit
measurement.

The reason for using an insulation tester to do tests like this is that the
battery voltage in your standard multimeter will not supply enough current
to effectively complete a circuit round the length of cables that you are
testing and also by generating 500v using the insulation tester you will
break down any potential shorting hazards so that they appear as a short in
the test where a multimeter will not.

These testers are not very expensive these days, I replaced my wind up hand
generator type with a nice new battery operated one from Maplins a number
of
years ago for about £35.

Just one other point and this one applies to anyone who works on electrical
installations.

When the 16th Edition of the regulations came out they were the first set
of
electrical regulations which were supported in law, i.e. the last person to
work on any electrical installation especially where funds are involved is
accountable in law should anything happen as a result of their work. I
don't
think I need to expand this any more it speaks for itself. Not quite Corgi
but pretty close.

Regards Paul H