Wireways sizing and the rules for junction boxes

[Carultch]

Do the 314.28 rules for junction boxes apply to laying out conduits in a wireway or wire trough?

I'm looking at a situation where I'm taking two 4" conduits thru the rear wall of the trough and converting them into two downward 4" conduits, using a top access trough. The rear 4" conduits are too close together where they have to enter a panelboard, in order to construct the adjacent roof penetrations. I'm trying to achieve some field flexibility for where the conduits can go through the roof.

I'm wondering if it is acceptable for a 4" conduit to enter an enclosure, only to have about 6 or 8 inches until it hits the opposite wall.
I'm also wondering if it is essential that the conduits be 24" away from one another. 6*4" = 24". So this could mean a 5 ft trough with the downward penetrations in the first two feet, and the rear exits in the final foot.

 

[Smart $]

See 37x.23 in wireway articles.

 

[Carultch]

See 37x.23 in wireway articles.

OK, I think this answers it. The distances between raceways need to be 24" apart just like pull boxes, but there is no issue with the wireway wall opposite a raceway entry being significantly smaller than 24", provided it is sized as wireways are sized for conductors in their cross section.

 

[Smart $]

OK, I think this answers it. The distances between raceways need to be 24" apart just like pull boxes, but there is no issue with the wireway wall opposite a raceway entry being significantly smaller than 24", provided it is sized as wireways are sized for conductors in their cross section.

Don't forget about sizing if [any] wire is deflected. The "across" dimension minimum is then the minimum wire-bending space per Table 312.6(A) for the deflected conductor size.