Box or trough U pull

[conmgt]

Hello,
Just want to verify something. I need to make a U pull of paralled 1/0 in 2" EMT. The raceways are 12" apart centerline to centerline. Is centerline the measuring point or is it raceway's edge to edge?

Also, I want to verify that my choices could be either a screw cover box...min 12" in the direction opposite the entering raceways...or a trough/wireway with the removable cover opposite of the entering raceways and is at least 3.5" deep. Correct?

One more please. This is a 4w 3ph feeder. The neutral is non current carrying...correct?

Thanks

 

[raider1]

I would say the distance between the raceways would need to be edge to edge and not center to center.

Also check out 310.15(B)(4) for when a neutral would be considered a current carrying conductor for apacity adjustment purposes.

Chris

 

[Dennis Alwon]

Here is a graphic for a U pull.

 

[augie47]

The heading of your thread: "Box or through" brings out, what to me, is an interesting discrepancy in the NEC.
As Dennis illustrates, with pull BOX the distance to the opposite wall must be 6X the conduit dimension.
However, if the same pull is used with a metallic wireway, 376.23 specifically says "between conduit entries" and does not mention "opposite wall". The 6X requirement to the opposite wall will vary by inspector.

In regard to your specific question, I have always considered the measurement to be to the edge of the conduits but that is because of illustrations and not wording.