Bundling

[pgordon]

Do I have to de-rate if i bundle (re:tie wrap), 10,15,20,or more 12-2 romex ? 310-15 2a.
how about mc ? 310-15 2a ex#5 ?
Please advise . not sure, thank you. PG

 

[infinity]

For NM cable the answer is yes for all cables. For #12 MC cable the first 20 CCC's are free. After 20 CCC's you'll need to derate.

 

[Dennis Alwon]

Most inspectors will make you derate for the nm cable. As for mc- I thought that was good for up to 20 cables before bundling took affect. I'm looking for the article. Here it is 310.15(B) except. 5