Ron,
On all of the modern 2 wire appliances that I have, there is no exposed
metal - it is all plastic or otherwise insulated.
There was an appliance designation that is termed "Double Insulated"
that used to be in common use. Double Insulated devices depend on the
fact that you cannot touch any part the can connect ot the electrical
circuits, even under fault conditions, and no 3rd ground wire is
required for them.
The equipment of the 40s and 50s often used metal cases that were
connected to nothing - until a fault occurred. I used to have some of
those old drills that produced quite a 'tickle' when operated outside or
if slightly damp. That was when I was much younger, and I sometimes
wonder how I survived, but am glad I did.
73,
Don W3FPR
Ron D'Eau Claire wrote:
Has anyone noticed how little that "safety ground" is used by commercial
products these days?
Few, if any, household appliances such as vacuum cleaners or even kitchen
appliances use it now. They all have two-wire plugs. For outdoor use I have
a electric chain saw, and electric circular saw, an electric weed-whacker,
an electric lawn mower and an electric hedge trimmer NONE of which use a
3-wire cord. They were all purchased in the last five years.
All of these devices revert to the standards of the 1940's and 50's, relying
on insulation without a "safety ground" tied to a metal enclosure. The
insulation is probably better than was used in the old gear, but it's the
same old design.
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