Aside… I believe ‘ise’s smooth-faced black 20-amp 3-pole device is a NEMA 10-20P configuration, formally termed 125/250 volts, 20 amperes, 3-pole, 3-wire [er, no equipment ground.] Before later “U-ground” wiring-device configurations, {1960s?} they were common out west for window air conditioners and portable electric room heaters. {This was when electricity was 1.6¢/kWh. Lived in a rural house with one such heater… 4500 watts, and my first month's electric bill came in at $35+. Heart Attack!!}
A slang term for the NEMA 10-20 receptacle was “crowfoot”. It was junior to the nongrounding NEMA 10-30 and 10-50 3-wire devices—still widely in service for cord-connected electric clothes dryers and electric ranges.
[This message has been edited by Bjarney (edited 06-02-2003).]
