[Elecraft] Much OT - No "practical" solution
Ron D'Eau Claire
ron at cobi.biz
Sun Nov 25 19:45:00 EST 2007
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.
Most of these devices have a polarized plug. The wide spade on the US plug
is the neutral or grounded side of the mains circuit. Presumably (I haven't
opened any of them up) they are wired so that a likely short to the metal
parts would be on that side of the mains. That's also how it was done in the
1940's and 50's.
Sure, I check to make sure the safety ground is attached to my household
outlets. It's astonishing how many outlets I've encountered over the years,
even in new homes, have no ground connection to the third pin. And many more
are wired backwards so if one puts a polarized plug in the outlet the wrong
(hot) side of the mains goes to the normally grounded side.
Frankly, I pay at least as much attention to the correct wiring of the mains
plug to put neutral on the wide spade as I do about the ground lead being
connected.
A little three-light tester available at most hardware stores for a few
dollars is well worth the investment.
Ron AC7AC
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