Need help sizing a box

[Flawild]

I have two 3” inch EMT’s entering and leaving a splice box from the same side. Two in, and two out.
need help properly Sizing the box.

 

[xformer]

See 314.28 (A) (2)

 

[Dennis Alwon]

Here is a good graphic

 

[ActionDave]

6 times 3 = 18 plus 2 additional 3 inch conduits equals 24" in this case.

 

[jusme123]

6 times 3 = 18 plus 2 additional 3 inch conduits equals 24" in this case.

If you do the math, that puts your knockouts literally at the corner of the box
18” between conduits + 3” conduit + 3” conduit = 24” exactly.

 

[sameguy]

I go bigger labor cost more than materials.