Help sizing trough

[Amal]

Looking for some help sizing a trough for a 600 amp 3 phase service, I have 2-4" conduits entering trough and 2-4" conduits leaving trough with 8-350 kcmil (4 in each conduit). I think 314.28 is required but not sure how the get calculation on minimum size and length. Any help would be greatly appreciated.

 

[Smart $]

Welcome :thumbsup:

Your 4" conduit is going to cause excessive size. Minimum is 24" wide trough, assuming side entry... and you'll have to add 4" for every conduit in a row... so it could be up to 36" wide to comply. If you stagger or otherwise arrange front to back by pair (in and out), you'd still be looking at 28".

With that said, you can get 4-350's THWN/-2 and a ground in 2-1/2" EMT or 3" RMC/PVC. That would cut your minimum down to 15" or 18" respectively, plus another width of conduit for every other entry in a row.

Probably an instance where you should consider installing the trough as an auxiliary gutter rather than using it as a wireway raceway/pull box...

 

[iwire]

Probably an instance where you should consider installing the trough as an auxiliary gutter rather than using it as a wireway raceway/pull box...

 

[liquidtite]

What's the difference between a trough as a raceway and using as a auxiliary gutter

 

[Smart $]

What's the difference between a trough as a raceway and using as a auxiliary gutter

Start at this post:

http://forums.mikeholt.com/showthread.php?t=161657&p=1569535#post1569535

...and go forward or backward in the thread as needed.