"mc" wrote in message
...
I can't speak for the rest of the world, but AIUI here in the UK such
safety devices work by detecting an inconsistency between live current
and neutral current, which would indicate some current is flowing to
earth, either through a human being or other fault condition. It works
just as well for two wire as three wire devices, and in fact the device
doesn't care or know one way or the other.

Right, but still not much of a help with an electric blanket, since there
is unlikely to be another path to ground. The hazards a (1) a fire, or
(2) person in bed making electrical contact with the heating element at 2
points that are at substantially different voltages.


If there's no other path to ground - getting electrocuted might be
difficult!