Leespark57
Senior Member
- Location
- Boston, MA, USA
I'm hoping to get some clarification on sizing wireways (troughs). The scenario in question would be a trough above 2 pieces of equipment with a 2" raceway entering from the top of the trough and (2) 1-1/4" raceways out the bottom feeding 2 panels. Since conductors in the raceways will be #4 or larger it states in 376.23(B) that 314.28(a) shall apply, which would require a minimum dimension of a 16" tall wireway.
(B) Metal Wireways Used as Pull Boxes.
Where insulated conductors 4 AWG or larger are pulled through a wireway, the distance between raceway and cable entries enclosing the same conductor shall not be less than that required by 314.28(A)(1) for straight pulls and 314.28(A)(2) for angle pulls. When transposing cable size into raceway size, the minimum metric designator (trade size) raceway required for the number and size of conductors in the cable shall be used.
Let's say you have 3/0 copper coming in and #3 copper tap conductors feeding the panels. Since the conductors are being spliced and not just passing through would 314.28 not apply because the raceways are not "enclosing the same conductors"? Otherwise, it seems like this is a rule that is often violated.
(B) Metal Wireways Used as Pull Boxes.
Where insulated conductors 4 AWG or larger are pulled through a wireway, the distance between raceway and cable entries enclosing the same conductor shall not be less than that required by 314.28(A)(1) for straight pulls and 314.28(A)(2) for angle pulls. When transposing cable size into raceway size, the minimum metric designator (trade size) raceway required for the number and size of conductors in the cable shall be used.
Let's say you have 3/0 copper coming in and #3 copper tap conductors feeding the panels. Since the conductors are being spliced and not just passing through would 314.28 not apply because the raceways are not "enclosing the same conductors"? Otherwise, it seems like this is a rule that is often violated.
