In message , Mike Tomlinson
writes
En el artículo , geoff troll@uk-
diy.org escribió:

"I AM A VERY NAUGHTY BOY AND I SHALL NEVER MEASURE MAINS VOLTAGES WITH
RESPECT TO EARTH AGAIN"

Why not? (not arguing, just want to understand)

If nothing else, it confirms that earth is earth.

Example: troubleshooting a hypothetical faulty appliance, at the
appliance I measure 240v between L and N, and 0v between L and E.
Either the flex is 2-core or there is an earth problem somewhere.


Live is referenced to Neutral full stop

There is no requirement for earth to be at any fixed potential wrt
either, and as the OP discovered, you can get false, misleading results

It doesn't confirm that earth is anything wrt anything else


--
geoff