On Tue, 26 Jun 2007 02:06:02 -0700, Seán O'Leathlóbhair
put finger to keyboard and composed:

I can also use a multimeter and one of those neon screwdrivers to
perform some more tests. Sticking the probes of the multimeter into
the light socket sounds a little scary. This is a UK lamp socket
which may be unfamiliar to US readers and some others. The bulb does
not screw in it is a bayonet mount. You push the bulb in and turn and
a couple or prongs catch the mount and hold the bulb. The contacts
are two sprung pins which press onto contacts at the bottom of the
bulb. The collar is metal. To UK readers and others who know the
system: is the collar connected to anything? If my multimeter probe
touches a contact and the collar, is something nasty going to happen?
Obviously if both probes touch their contacts and the collar,
something nasty may happen.

I've just checked the Australian fittings. Our new batten holders have
bakelite collars, but the old ones were metal. There is no continuity
between the collar and any other terminal, including the earth
terminal (which doesn't exist on some fittings).

- Franc Zabkar
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