On Thu, 10 May 2007 23:57:52 +0100, John Rumm
wrote:

Drake wrote:

Anyway, thanks to all for the input. I'd still like to know why the
thing lit up when touched on junction box terminals after the fuse for
that circuit was removed, and on all three too (including earth) -
when a volt meter registered 0 volts.

Its called inductive coupling. The wires probably run some distance in
proximity to other wires which are live. Although there is no physical
connection between them the alternating magnetic field produced by the
current flowing in the live circuit will induce a voltage in the
disconnected one. (same principle by which a transformer works)

Ah, yes. I know for a fact that the cable leading to that circuit does
run close to other cables for some distance. Thanks for the education!

Drake