i have a dumb question

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responder1

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where can i find in the nec that i have to derate aluminum? i have been hearing about it and im looking for it. i work so much i dont have time to look it up often. thanks
 
responder1 said:
where can i find in the nec that i have to derate aluminum? i have been hearing about it and im looking for it. i work so much i dont have time to look it up often. thanks
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Table 310.16
 
i was talking to an inspector and he said i cant go in the 75 degree colum to size my wire. i have to use the 60 degree colum
 
responder1 said:
i was talking to an inspector and he said i cant go in the 75 degree colum to size my wire. i have to use the 60 degree colum
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Are you using se cable??? Look at 338.10
 
i agree about using wire if the terminals is rated for 75 degree's. but i have been hearing that for service cables like 2 or three conductor has to be derated to the 60 degree colum
 
responder1 said:
i agree about using wire if the terminals is rated for 75 degree's. but i have been hearing that for service cables like 2 or three conductor has to be derated to the 60 degree colum
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You have heard correctly 334.80 as Dennis pointed out.

By the way it is not 'derating' it is just 'the rating'
 
responder1 said:
i agree about using wire if the terminals is rated for 75 degree's. but i have been hearing that for service cables like 2 or three conductor has to be derated to the 60 degree colum
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Forget the statements above-- they have nothing to do with this issue.

Here

338.10(B)4) Installation Methods for Branch Circuits and Feeders.
(a) Interior Installations. In addition to the provisions of this article, Type SE service-entrance cable used for interior wiring shall comply with the installation requirements of Part II of Article 334.

334.80 Ampacity.
The ampacity of Types NM, NMC, and NMS cable shall be determined in accordance with 310.15. The ampacity shall be in accordance with the 60?C (140?F) conductor temperature rating. The 90?C (194?F) rating shall be permitted to be used for ampacity derating purposes, provided the final derated ampacity does not exceed that for a 60?C (140?F) rated conductor. The ampacity of Types NM, NMC, and NMS cable installed in cable tray shall be determined in accordance with 392.11.
Where more than two NM cables containing two or more current-carrying conductors are installed, without maintaining spacing between the cables, through the same opening in wood framing that is to be fire- or draft-stopped using thermal insulation, caulk, or sealing foam, the allowable ampacity of each conductor shall be adjusted in accordance with Table 310.15(B)(2)(a) and the provisions of 310.15(A)(2), Exception, shall not apply.
Where more than two NM cables containing two or more current-carrying conductors are installed in contact with thermal insulation without maintaining spacing between cables, the allowable ampacity of each conductor shall be adjusted in accordance with Table 310.15(B)(2)(a).
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