D dana1028 Senior Member Location San Francisco Bay area Sep 3, 2012 #1 I have THHW installed underground [75 degree col.]....but for derating purposes [conduit fill] do I start in the 75- or the 90-degree column?
I have THHW installed underground [75 degree col.]....but for derating purposes [conduit fill] do I start in the 75- or the 90-degree column?
sparky_magoo Senior Member Location Reno Sep 3, 2012 #2 75 degree 75 degree 75 degree in a wet location.
Dennis Alwon Moderator Staff member Location Chapel Hill, NC Occupation Retired Electrical Contractor Sep 3, 2012 #3 Good question. IMO you would have to start at the 75C rating
infinity Moderator Staff member Location New Jersey Occupation Journeyman Electrician Sep 3, 2012 #4 Just double check and make sure that it's not listed as THWN-2. THWN-2 is a 90? C conductor even in wet locations.
Just double check and make sure that it's not listed as THWN-2. THWN-2 is a 90? C conductor even in wet locations.
D dana1028 Senior Member Location San Francisco Bay area Sep 3, 2012 #5 Thanx all - that is what I thought, just wanted to make sure [it is THHW] of the starting point.
kbsparky Senior Member Location Delmarva, USA Sep 3, 2012 #6 THHW is unusual but a valid listing in the NEC ...
infinity Moderator Staff member Location New Jersey Occupation Journeyman Electrician Sep 3, 2012 #7 Disregard my first post. I thought that we were discussing THWN. :ashamed1: