On 7/18/2017 2:40 PM, John Rumm wrote:
On 18/07/2017 12:47, Martin Brown wrote:
On 18/07/2017 11:48, DerbyBorn wrote:

I got involved with someone who was wiring a external LED Floodlight
into
some old wiring.

The light didn't work and from a brief tracing of the cable back to the
switch I suspect it has 2 lives.

You would expect switched live and a neutral.

Question:

Can I use my cheap digital meter to check between live and earth to
prove
this? Could it trip an ELCB if there is one (not checked yet)

It would be wiser to measure from live to neutral if at all possible. I
doubt that a decent high impedance voltmeter would trip an ELCB but you
have to consider the possibility that your leads are less than perfect.

I prefer a good old mains testing neon screwdriver (even though they are
frowned upon these days). If the neon glows it ain't safe to touch.

With those, if it glows its either live or dead. If it doesn't glow then
its definitely either live or dead.

You call ;-)


The thing that I like about volt sticks is that you are not waving a bit
of metal against and around other bits of metal which could be either
live, neutral, or earthed.

That said, I have known volt sticks not play at one moment, then work
fine the next. I think both volt sticks and neons have their place.

Most important is a healthy amount of caution on the part of the person
holding them. Less so if you are *sure* you have RCD protection, as long
as you remember that this is no help if you touch live and neutral at
the same time.

On Wednesday, 26 July 2017 22:10:42 UTC+1, rick wrote:
On 18/07/2017 12:47, Martin Brown wrote:
o consider the possibility that your leads are less than perfect.

I prefer a good old mains testing neon screwdriver (even though they are
frowned upon these days). If the neon glows it ain't safe to touch.


The problem is the failure mode ... if neon blows a user can assume no
glow = safe

But I do have some more than 40 years old still working - so pretty
reliable.

For most things I use a Digital Multimeter or a Martindale Tester (I
know this is neon - but lots of them)

that is not the problem and they are not reliable


NT

On 26/07/2017 23:00, wrote:
On Wednesday, 26 July 2017 22:10:42 UTC+1, rick wrote:
On 18/07/2017 12:47, Martin Brown wrote:
o consider the possibility that your leads are less than perfect.

I prefer a good old mains testing neon screwdriver (even though they are
frowned upon these days). If the neon glows it ain't safe to touch.


The problem is the failure mode ... if neon blows a user can assume no
glow = safe

But I do have some more than 40 years old still working - so pretty
reliable.

For most things I use a Digital Multimeter or a Martindale Tester (I
know this is neon - but lots of them)

that is not the problem and they are not reliable


NT



what is not reliable ... a Martindale tester ? Had one for more than
25 years - works perfectly, they are standard items of test kit

On 26/07/2017 22:10, rick wrote:
On 18/07/2017 12:47, Martin Brown wrote:
o consider the possibility that your leads are less than perfect.

I prefer a good old mains testing neon screwdriver (even though they
are frowned upon these days). If the neon glows it ain't safe to touch.


The problem is the failure mode ... if neon blows a user can assume no
glow = safe

That's why with both neon screwdrivers and volt-sticks, it was always
test, show that it lights, isolate, test and show that it doesn't.

SteveW