Single Family Dwelling Service Conductors

[BLA]

When determining the max ampacity for a 200 amp 240 volt Aluminum service entrance conductors on a single family dwelling, which column on table 310.15 (B)(16) is used. I think it's the 75*c for aluminum but can't find the exact place where this is specified. I'm using the 2014 NEC in Virginia.

 

[charlie b]

You do use the 75C table for aluminum, presuming your conductors have an insulation system rated 75C or 90C. But you don't have to size them for 200 amps. 310.15(B)(7)(1) allows you to size them at 83% of the service rating. That means you need an ampacity of 166 amps, and that a 4/0 will suffice (rather than 20 KCMIL).

The "exact place" you seek is the first paragraph of 310.15(B).

 

[BLA]

Thank you. Article 338 in previous codes stated that the conductors in a SE cable must be rated 60*c like NM. Am I mistaken?

 

[Dennis Alwon]

Thank you. Article 338 in previous codes stated that the conductors in a SE cable must be rated 60*c like NM. Am I mistaken?

That is correct.