In article , NY
wrote:
"Martin Bonner" wrote in message
...
Are US and European plugs capable of having a fuse fitted in them
No

or do their appliances always blow the circuit (eg downstairs ring
main)
What ring main? Everything is wired as (chained) radials. But yes,
the only fuse is in the consumer unit.

Are ring mains mainly a UK innovation, then? I hadn't realised that.

Either way, if an appliance develops a fault, it is normal that
everything fed by the same fuse or circuit breaker will fail, rather
than (hopefully) only that appliance failing and everything else staying
on. Now THAT is a colossal retrograde step: the thought that a short in
a table lamp or a PC power supply could disable my deep freeze when I
was out and unable to replace the fuse doesn't bear thinking about. I'm
surprised that when we in the UK went from unfused to fused plugs, other
countries didn't see that advantage and make the same change.

One of the few places where old unfused round-pin plugs are still used
today is in theatre/TV lighting where it's much easier to change a fuse
on the lighting board rather than one up above the stage where each
light is plugged into its circuit.



Do 240V and 120V bulbs have identical-sized screw threads, or are they
deliberately incompatible sizes to avoid putting a 120V bulb in a 240V
fitting?
No idea, but I would guess from the name ("Edison") that they are
identical.

I think there are various different diameters of ES (maybe all with the
same pitch of thread) but I wonder if this is enforced so that bulbs
that are rated for different voltages can never be interchanged in the
same light fitting (ie to prevent you accidentally using a US bulb in
European mains). The real problem arises if you bring a US table lamp
back to Europe and simply change its mains plug - now you wouldn't be
protected by the diameter/voltage restirctions!

We had 12v ES emergency lights in our theatre. They used quite standard ES
theads. Confused some people sometimes.

--
from KT24 in Surrey, England