314.28 Question

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augie47

augie47

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In the dated MH slide below Dimension "A" shows as being 18" based on the (1) 3" entering the right hand wall. 314.28 states "The distance between raceway entries enclosing thesame conductor shall not be less than six times the metric designator (trade size) of the larger raceway" in which case the 18" would not provide enough distance to provide 6X the distance between raceways. Does the quoted section not apply since the conductors are spliced and not necessarily the "same conductor" ?



doc3.jpg
 
Straight pulls are supposed to be 8 x

(1) Straight Pulls. In straight pulls, the length of the box
or conduit body shall not be less than eight times the metric
designator (trade size) of the largest raceway.
Click to expand...
 
augie47 said:
In the dated MH slide below Dimension "A" shows as being 18" based on the (1) 3" entering the right hand wall. 314.28 states "The distance between raceway entries enclosing thesame conductor shall not be less than six times the metric designator (trade size) of the larger raceway" in which case the 18" would not provide enough distance to provide 6X the distance between raceways. Does the quoted section not apply since the conductors are spliced and not necessarily the "same conductor" ?
View attachment 18629
Click to expand...

The single conduit on the right does not have other conduits on the same wall so the distance between the entry and the opposite wall is just 6x.

IMO, since the the enclosure is being used as a junction point and not a angle pull the distance between the right and the bottom conduits do not have to be 6x the largest conduit.
 
Altho not an answer, istm that speccing 24 x 24" boxes when 3" conduits are used or 32 x 32" (or larger) with 4" would eliminate any guesswork re: code or in what orientation the conduits enter. You have 8x no matter what then. Is there a big difference in price? I dont see any labor-wise.
 
JFletcher said:
Altho not an answer, istm that speccing 24 x 24" boxes when 3" conduits are used or 32 x 32" (or larger) with 4" would eliminate any guesswork re: code or in what orientation the conduits enter. You have 8x no matter what then. Is there a big difference in price? I dont see any labor-wise.
Click to expand...

It is not a matter of cost or what size enclosure is available but rather what is the correct way/answer.
 
augie47 said:
In the dated MH slide below Dimension "A" shows as being 18" based on the (1) 3" entering the right hand wall. 314.28 states "The distance between raceway entries enclosing thesame conductor shall not be less than six times the metric designator (trade size) of the larger raceway" in which case the 18" would not provide enough distance to provide 6X the distance between raceways. Does the quoted section not apply since the conductors are spliced and not necessarily the "same conductor" ?
Click to expand...
It does apply. But the depiction is not for that purpose. In addition, the drawing is not to scale. Note enclosure appears square yet notes say 24 x 18 required. In reality, with a 24 x 18 box, it very well could be 18" from right-side conduit entry to middle-bottom entry.
 
Smart $ said:
It does apply. But the depiction is not for that purpose. In addition, the drawing is not to scale. Note enclosure appears square yet notes say 24 x 18 required. In reality, with a 24 x 18 box, it very well could be 18" from right-side conduit entry to middle-bottom entry.
Click to expand...

Why does the 6x rule apply if it is a splice box? The 6x applies if it is the same conductor and it is a pull through. I am not correct?
 
edward said:
Why does the 6x rule apply if it is a splice box? The 6x applies if it is the same conductor and it is a pull through. I am not correct?
Click to expand...
The title of 314.28(A)(2) Angle or U Pulls, or Splices.

As to a justification by way of physics, I can't offer one. ;)
 
Smart $ said:
It does apply. But the depiction is not for that purpose. In addition, the drawing is not to scale. Note enclosure appears square yet notes say 24 x 18 required. In reality, with a 24 x 18 box, it very well could be 18" from right-side conduit entry to middle-bottom entry.
Click to expand...

Despite scale, if dimension "A" is 18" there is no way there can be 18" between the left bottom conduit and the right conduit both of which have a common conductor which lead me to question if the 6X rule between conduits applied to spliced conductors or only to unspliced conductors occupying common conduits.
 
Screen Shot 2017-09-28 at 8.16.29 PM.jpg

IMO, the distance between 3&4 is not 18" and does not have to be 18" because the conduits do not house the same conductors.

The distance between the 1&3 has to be 18" because you can argue it is the same conductor. And one can argue that they are not the same conductor.

And distance between 2&4 same as above. Could argue the conduits do not house the same conductor some may say it does.
 
augie47 said:
Despite scale, if dimension "A" is 18" there is no way there can be 18" between the left bottom conduit and the right conduit both of which have a common conductor which lead me to question if the 6X rule between conduits applied to spliced conductors or only to unspliced conductors occupying common conduits.
Click to expand...
If dimension B has to be 24". If right conduit bottom is 6" down from top, then it is at least 18" from bottom-center conduit right side.

The problem is there is definitely not 18" between conduits with black and blue conductors, as you point out.

Personally, I'd like to see the requirement changed for spliced conductors.
 
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