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Re: AC polarity



Ummm. I dono David, If the tool is UL Listed this won't happen. Either
one of the prongs is bigger so it will only fit in the long hole or the case
is "double insulated" -- like Sears tools -- those can be plugged in either
way because the case is NOT connected. If the appliance is not UL listed
all bets are off. If I remember correctly UL does not allow either the
neutral or the hot to be connected to the case. But this is good to think
about just in case. There is always some twitty home owner (or twitty
electrician) who has wired incorrectly.

Jim



One place where it matters is with devices that are internally grounded.
Since all houses are supposed to be wired with the same slot connected to
ground, some appliances, rather than using a third wire connected to the
round ground terminal, just use two wires and connect the one that is susposed
to be the house ground to the case or chasis of the appliance. This is very
common with hand tools. If you now stick the plug in backwards reversing the
polarity, the case is hot.