ampacities for conductors

[excelelectric215]

I was taged for the 1st time by a local inspector, for having to many romex's in a 2"pvc sleave entering a panel. Is there anyone here that can explain and help me understand how to do the calculation to figure the proper adjustment factors. I have been looking in the code at Table 310-15 (B) (2) (a) and im stumped, I hope i can be set straight
Thanks

 

[augie47]

There are restrictions other than derating concerning sleeving NM into a panel (see 312.5), but in answer to your question, determine how many current carrying conductors you have (a 2 conductor NM would have 2, a 3 conductor sharing a neutral would be 2, etc) and apply the derating factors in 310.15(b)(2)(a) to the 90? rating. (For example, the 10th cc conductor would reduce #12 to 15 amps)

 

[infinity]

How many cables did you have and what size are they? How long was the PVC sleeve?

 

[Pierre C Belarge]

This could be a pipe fill and an ampacity adjustment issue.

 

[quogueelectric]

Pipe fill is usually close to as many as you could possibly fit with thhn ratings. Going over 9cccs however can really cost you from my understanding now. It is rarely caught or even understood in my area. It is still standard practice for a 2' piece of trough above a panel with 2 -2" pipes entering left for odd ckts right for even ckts.