20% fill vs 30 current carring conductors

[Dbronx]

There is a 80 foot 4 X 4 metal wireway with 41 # 12 conductors installed in it, 41 #12 wires = 3% of the wireway area. Would that be a code violation because there are more than 30 wires in a cross section?

 

[Dennis Alwon]

You cannot exceed 20% of the wireway cross section but you need to derate when you exceed 30 CC conductors. 376.22(B)

 

[Dennis Alwon]

From what I see this means the #12 are now only 30 amps times .35= 10.5 amps

 

[augie47]

It could be,
Are they all "current carrying conductors" or are some neutrals that don't qualify as ccc's ?
Are there over 30 ccc's at every cross section of the wireway ? (If you sliced the wireway like bread and pulled sections out, would that section have over 30? )

 

[Dbronx]

Since they are 20 dedicated nonlinar loads circuits, the neutrals should not be considered current carring conductor. That would mean only 20 current carring conductors in raceway and no derating nessary, is that correct.

 

[Smart $]

Since they are 20 dedicated nonlinar loads circuits, the neutrals should not be considered current carring conductor. That would mean only 20 current carring conductors in raceway and no derating nessary, is that correct.

dedicated = individual ? ...as in one hot and one neutral per circuit. If so, these neutrals always count, regardless of other issues.

 

[Dbronx]

Much thanks Dennis Alwon, augie47 and Smart$ It looks like some larger wire needs to be pulled for these 20 amp recepticals.

 

[petersonra]

Much thanks Dennis Alwon, augie47 and Smart$ It looks like some larger wire needs to be pulled for these 20 amp recepticals.

it might be cheaper to just put a divider downt he center of the raceway and split it into two chunks.

 

[Dennis Alwon]

If you used a common neutral with 3 conductors on different phases then you would not count the neutral unless this is fluorescent lighting or computer type loads(non linear)

 

[Smart $]

it might be cheaper to just put a divider downt he center of the raceway and split it into two chunks.

I don't believe installing a divider will magically make one wireway qualify as two... :happysad:

 

[Smart $]

If you used a common neutral with 3 conductors on different phases then you would not count the neutral unless this is fluorescent lighting or computer type loads(non linear)

Even if the neutral did count, the overall count would drop: 20? + 7N = 27CCC. Code compliant with breaker handle ties. Meets spec's and other non-NEC issues???

 

[petersonra]

I don't believe installing a divider will magically make one wireway qualify as two... :happysad:

why wouldn't it? it is two seperate places for wires to run.

it is listed that way for seperating different voltage levels of conductors, so it has to be seperate raceways.

 

[Smart $]

why wouldn't it? it is two seperate places for wires to run.

it is listed that way for seperating different voltage levels of conductors, so it has to be seperate raceways.

Perhaps separate(d) raceways... but the ampacity requirement is for the "wireway", not per "raceway".