High Temp Wire

[dstan02]

In the code, under the tables "Section 310", I am trying to research the properties of 1,000V, 125C, XLPE wire. The question is, that it appears in the code that high temp wire such as 12, 10 AWG does not have the breaker limitation footnote as under the 90C and below listing. Can anyone confirm and / or direct me to a statement that allows the use of 12 or 10 AWG HIGH TEMP WIRE such as XLPE with out being limited to the breaker size. IE " 12 using no larger than a 20A breaker, etc."

 

[wanderer20001us]

Re: High Temp Wire

I am not aware of any exception to 240.4(D) except as listed in (E) - (G). On these size conductor, the higher temp ratings can only be taken advantage of to offset the derating requirements of 310.15(B)(2).

What is the application?

Sam A. - PE

 

[dstan02]

Re: High Temp Wire

The question comes up if you look at tables 310-16 to 17 that show a footnote for 90C wires 10,12,14. When you get to the higher temp wires of 125, 150, 200 C etc. as on table 310-18 to 19, that breaker limitation foot note goes away. So the question still applies that even though the table eleminates the breaker note, can anyone direct me to a specific paragraph that explains the high temp use ?

 

[wanderer20001us]

Re: High Temp Wire

The absence of the foot note should not be a license to violate 240.4. If the application does not fit 240.4(E), (F), or (G), 240.4(D) applies.