Conduits exposed to the sunlight on rooftops

[chocho77]

Can anybody clarify what is the "Ambient temperature" when using Table 310.15 (B)(2)(c) for Seattle for example?

 

[hardworkingstiff]

Maybe this can help?

http://www.copper.org/applications/electrical/building/derating_table.html#WA

 

[chocho77]

Thank you!
Why there are two columns 12" Distance above roof?

 

[hardworkingstiff]

Thank you!
Why there are two columns 12" Distance above roof?

Typo, if you go up to the top of the page you will see the 1st column is listed as 1/2". That matches the distances in Table 310.15(B)(2)(c).

Good catch!

 

[chocho77]

Yes, I already got it!
Thank you, sir!

 

[W6SJK]

Thanks for the link! I wrote the webmaster to report the error.