Thank goodness that Home Depot and Lowe's stock #10 stranded copper THWN wire and are willing to cut it. The issue of color coding was a big issue when doing a 30-amp circuit in EMT and the commercial building owner cannot afford to buy 3 reels of #10 stranded wire and then use only 1/8 or 1/4 of each reel of white and green. On industrail jobs this was not quite so big of an issue because usually there are a lot more in the way of 30-amp circuits.
For a long time most supply houses would not cut #10 THWN and Lowe's and Home Depot would only stock SOLID #10 THWN copper wire.
Back in the 1970s a different issue was that when using EMT for home runs in a dwelling I had to use #10 THWN for 20-amp circuits because of the 60 degree Celsius limitation of romex back then. Still an issue when installing a new service right nest to the old one.
One way out of this ( and not very satisfactory ) was to substitue #8 stranded wire which most supply houses would cut. Michael R. Cole Reply to this comment |