Hi again Chuck,
My copy of NEC is at work, so I cannot check out the actual text of NEC
today. I found this on the internet:
At one time, the code allowed for one insulated wire to function as
both ground and neutral in 120 / 240 volt combo circuits, but now all
such circuits must use the 4 wire scheme. This is why your new dryer
(or electric range) might have 4 prongs on its plug and your old dryer
receptacle only has 3 holes. In which case article 250.140 of the 2005
N.E.C. (National Electric Code) allows for the "pigtail" (the cord and
plug assembly) to be changed to match the old 3 wire receptacle as
long as certain conditions are met. The National Electric Code allows
that, but your local code might not, so check first, or even better
yet make a deal with the appliance dealer to do it for you.
So then, you are correct, one upon a time it was allowed. I apologize
for saying "Connecting a 110 volt load between a hot lead and ground IS
NEVER, EVER ACCEPTABLE!". There is good reason the code was changed, so
even if it was once allowed, I would never, ever recommend connecting a
120 volt load between a hot lead and the ground lead. You will not find
anything operating that way in my home.
DE N6KB
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