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More on wiring a reverse-polarity alarm  To the editor: In the
question and answer column in a recent issue ("Wiring a reverse
polarity alarm," March/April 2000, Issue No. 104), I believe
paragraphs two and three of Chuck Husick's answer to the
question need further explanation. Taking paragraph three first,
it is not true that one of the two conductors is arbitrarily
called the hot, or black, wire. A typical domestic (or marina)
power distribution system starts with a three-wire 120/240 volt
output from a utility company transformer. The central or
neutral wire is grounded at the transformer, and again at the
customer's main service box. U.S. and international standards
call for this wire to be colored white. The other two wires are
typically black and red, and the voltage between either of these
wires and the white or grounded neutral wire is 120 volts. The
voltage between the black and the red wire is 240 volts, which
is required for electric