314.28 Pull Box sizing when cable entry is opposite the removable cover

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adalewhite

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There are 3 sets of 4? conduits each with 4-600kCMIL conductors are required by the contract documents. Only two sets are installed at first and it is caught on a punch list and the third set is required to be installed. The follow up punch list reads ?While the third 4? conduit has been added to the service entrance, the pull box violates NEC 314.28. The box dimensions should be at least 4?X6=24?+4?+4?+32? in width and 8? deep per 314.28(A)(2) Exception reference to Table 312.6(A) for entry in the wall of box opposite a removable cover.? Is this a correct call? See the pictures.
Original Box.jpg Revised Box.jpg
 
adalewhite said:
There are 3 sets of 4? conduits each with 4-600kCMIL conductors are required by the contract documents. Only two sets are installed at first and it is caught on a punch list and the third set is required to be installed. The follow up punch list reads ?While the third 4? conduit has been added to the service entrance, the pull box violates NEC 314.28. The box dimensions should be at least 4?X6=24?+4?+4?+32? in width and 8? deep per 314.28(A)(2) Exception reference to Table 312.6(A) for entry in the wall of box opposite a removable cover.? Is this a correct call? See the pictures.
View attachment 8316 View attachment 8317
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The 8" deep looks right based on the exception, and under one interpretation the height of the box needs to be 4x6 + 4 + 4 = 32 based on 28(A)2 with no exception as a result of the bottom entries. There is no minimum size for the width AFAIK.
But that assumes that the word "row" is used in a way that applies to the three conduits. Since the section talks about multiple rows in the same side of the box, I would rather interpret it to mean, in this case, rows of conduits stacked from the front of the box toward the back. In that case you have three rows of one, and the height only needs to be 24", with no adders. When you think about how the presence of other entries and wires affects the size of the box needed for a clean pull, the second interpretation makes more sense. Is there an illustration in the Handbook that clarifies this?

The 8" depth requirement was there from the start.
 
I'd have to agree with the 32X32X8 interpretation. When you look at Exhibit 314.11 in the handbook it is pretty clear how to look at the rows. And since the 3-4" conduits are the only row it only leaves one way to look at the row. I appreciate the input and would like to hear more.
 
What about distance between raceway entries into that box? 314.28(A)(2) says "The distance between raceway entries enclosing the same conductor shall not be less than six times the metric designator (trade size) of the larger raceway."

Sure looks like they are closer than that in the photo of what was existing. What good does it do to require a 32" high box and then place the conduit entries for the same conductors only 8-10, inches, or even less away from one another in that same box?

If those are 600MCM conductors, they would be difficult to bend a tight bend like is shown in the photo, which is the reason why such a tall enclosure would be required.
 
copper chopper said:
in my opinion the exception to 314.28A overrides what Kwired is talking about. but this seems to be what the AHJ's interpretation of this is.
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That exception allows the depth of the box in the OP's installation to be less because of the removable cover, not the distance between raceway entries. If the top of the box also had a removable cover then you could also decrease the height of the box - but you still need 6 times the largest raceway between raceway entries enclosing the same conductors.
 
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