Conduit fill

[Vikingo1]

When I am adjusting the ampacity of a raceway that all ready have 3 current carrying conductor do I have to derate more for spares and travelers?

 

[Dennis Alwon]

When I am adjusting the ampacity of a raceway that all ready have 3 current carrying conductor do I have to derate more for spares and travelers?

The code makes no exception for travelers however the spares can be argued. IMO, they are not current carrying conductors but it may defeat the purpose of pulling them if the next guy has to derate when they energize them. The code is not clear but, IMO, it would be prudent to derate.

 

[don_resqcapt19]

I would never count both travelers...only one can carry current at a time and the deratiing is based on the number or current carrying conductors.

 

[ActionDave]

I agree. There is no exception in the code because there is no need. Only one traveler carries current at a time. Derating applies to number of current carrying conductors -period.

 

[KNT]

I think we have to look close now under table 310.15(B)(3)(a) in the 2011 code it says Number of conductors is the total number of conductors.

 

[infinity]

I think we have to look close now under table 310.15(B)(3)(a) in the 2011 code it says Number of conductors is the total number of conductors.

Read it again. This was just added to the 2011 to make it even more confusing. You need to also read notes 310.15(B)(5) and (6).

 

[Dennis Alwon]

You may get away without counting the travelers but the code states ccc. It does not say only count the ones that come on simultaneously.

 

[xformer]

I understand only counting the CCC's when derating.