"Unquestionably Confused" wrote in message
m...

NEC - National Electrical Code charts for just this thing. I only have
an old one but that's what it says for a 20amp, 240 volt single phase
circuit.

FWIW, checking the voltage without a load in place won't tell you squat.
It has to be under load.
As an example that same #12 wire is good for
280' with a load of 5 amps, and a qualified (depending on type of
insulation, conduit or cable, etc) 36' run at 40 amps.

#12 wire is not rated to carry 40A. #10 is not even rated to 40A. What are
we up to - #8? Man - that'd be one hefty cord. "Sure hon, you can help -
just coil up the power cord for the table saw while I sweep up, will ya?"...


Remember too that Tim was, I believe, referring to a 240 volt circuit.
With a 120 volt circuit #12 is good only for a run of 35'.


You have to be reading something wrong in the code book. If this was true,
there is not a house in America that is wired to code. Think of how many of
your circuits contain more than 35' of #12 wire. I'd look at it myself but
I don't have my code book (also an older edition) available right now.
Watch those current ratings.

--

-Mike-