When is a wireway defined as a pull box?

E

ESLLC

Member
Location
Pierce Co, WA
Occupation
contractor
We've received a correction from the AHJ stating that a 10" x 10" x 96" horizontal wireway installed below three panelboards (each being 24"wide x 9" deep) is a pull box and must be increased to 20" in height due to the fact that we have installed 2.5" conduits under-slab and up into the wireway. We then have 2.5"diameter x 3"long nipples connecting the wireway to the panelboards.
AHJ is saying that this is a pull box and that per NEC 314, the 2.5" conduit size x 8 for a straight pull through a pull box brings us to a "pull box" height of 20".
I believe this to be a wireway because the conductor pulling concludes once in the wireway and the conductors are then formed and fed up and through the conduit nipples into the panelboard.
What do you say?
My apologies, I've got a photo but apparently I'm not yet allowed to attach photos because I just joined.
 
ESLLC said:
We've received a correction from the AHJ stating that a 10" x 10" x 96" horizontal wireway installed below three panelboards (each being 24"wide x 9" deep) is a pull box and must be increased to 20" in height due to the fact that we have installed 2.5" conduits under-slab and up into the wireway. We then have 2.5"diameter x 3"long nipples connecting the wireway to the panelboards.
AHJ is saying that this is a pull box and that per NEC 314, the 2.5" conduit size x 8 for a straight pull through a pull box brings us to a "pull box" height of 20".
I believe this to be a wireway because the conductor pulling concludes once in the wireway and the conductors are then formed and fed up and through the conduit nipples into the panelboard.
What do you say?
My apologies, I've got a photo but apparently I'm not yet allowed to attach photos because I just joined.
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I think you have that backwards. If you are pulling in to the wireway, then that makes the wireway a pull point.
 
ESLLC said:
AHJ is saying that this is a pull box and that per NEC 314, the 2.5" conduit size x 8 for a straight pull through a pull box brings us to a "pull box" height of 20".
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What size conductors are you pulling in the 2.5" nipples? If smaller than #4 then then 8X rule doesn't apply.
 
Strathead said:
I think you have that backwards. If you are pulling in to the wireway, then that makes the wireway a pull point.
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I totally agree that it's a pull point, but I'm not pulling any further to make it a straight pull. It's at the terminus of the conduit run, not out in the middle of the run. The other end of the box has a 3 or 4 inch long nipple into the panel so obviously at that end we are forming and bending wire through a nipple. I thought for sure that would remove it from the 8x rule and place it into the wire bending radius tables. I've never seen a problem before with an 8x8 or 10x10 wireway below panelboards.
 
Strathead said:
which isn't legal.
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When I questioned his call, the inspector told me that had I run the conduits straight through the wireway we would be all good. That really surprised me. What do you use for numbers to calculate "conduit fill" within a wireway?!? I've never heard of trying to figure out "how much space did your conduit take up in the wireway". It certainly takes away from space left for conductors.
 
Eddie702 said:
I would like to know the answer to this as well as the 8x rule seems impossible.
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I have read 376.23 multiple times and, like many code sections, misread it. As I read it now (hopefully right this time). First off, when is a wireway a pull box? That is not defined, so the AHJ would get to make that determination, but I would say the OP has a fair argument, that when you are pulling in to it and then feeding out to, say a panel, it is a wireway and I withdraw my first comment from a code perspective. When you pull to it, then pull from it, it becomes a pull or junction box. As a wireway, you can use the deflection rules of 376.23(A). As a pull point you must use 376.23(B)
 
ESLLC said:
I totally agree that it's a pull point, but I'm not pulling any further to make it a straight pull. It's at the terminus of the conduit run, not out in the middle of the run. The other end of the box has a 3 or 4 inch long nipple into the panel so obviously at that end we are forming and bending wire through a nipple. I thought for sure that would remove it from the 8x rule and place it into the wire bending radius tables. I've never seen a problem before with an 8x8 or 10x10 wireway below panelboards.
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See my other post, I agree and believe I was wrong.
 
ESLLC said:
When I questioned his call, the inspector told me that had I run the conduits straight through the wireway we would be all good.
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Well that is one solution. IMO if the raceways entering the wireway are directly inline with the nipples I might let it go because you're not going to pull in and out of the wireway. For what it's worth this is a very common violation when using wireways above or below panels.
 
Strathead said:
I have read 376.23 multiple times and, like many code sections, misread it. As I read it now (hopefully right this time). First off, when is a wireway a pull box? That is not defined, so the AHJ would get to make that determination, but I would say the OP has a fair argument, that when you are pulling in to it and then feeding out to, say a panel, it is a wireway and I withdraw my first comment from a code perspective. When you pull to it, then pull from it, it becomes a pull or junction box. As a wireway, you can use the deflection rules of 376.23(A). As a pull point you must use 376.23(B)
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Pardon my ignorance, what is "OP"?

Yes, you've exactly nailed my point. It's only a straight pull situation if I'm pulling both in and out in a conduit. We're pulling in a conduit and forming and feeding conductors out through a nipple, not installing a rope to pull through that nipple! lol
 
Strathead said:
See my other post, I agree and believe I was wrong.
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Thank you Strathead, I appreciate that. Just wish I had an angle to convince the AHJ this is correct. It's going to be an expensive fix on a gorgeous install similar to so many others we've done just like it.
 
ESLLC said:
Pardon my ignorance, what is "OP"?

Yes, you've exactly nailed my point. It's only a straight pull situation if I'm pulling both in and out in a conduit. We're pulling in a conduit and forming and feeding conductors out through a nipple, not installing a rope to pull through that nipple! lol
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In this case you. The "original poster".
 
Strathead said:
Oops, read it wrong again. I misread 376.23(A)
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I'm actually using section 366. It's interesting to me that "wireways as a pull box" is a small paragraph nearing the end of the section. Like for the most part, wireways installed near panels are simply wireways as they are intended to be used and in my mind, when used as a pull box is out in the middle of a conduit run.
 
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