Nema 9 box

[ravenjoe]

I have a Class II Div 2 group F installation. Do my penetrations have to be threaded bosses for conduit. Am I interpreting 502.10(B) correctly? Drill and tap or pre-tapped from factory?

 

[don_resqcapt19]

Class II, Division 2 enclosures are not required to have threaded hubs or bosses. Often you find boxes that are dual listed for NEMA 7 and NEMA 9 and those boxes will have threaded connections.