pull box vs Wire ways

[mannyb]

are the requirements same the for sizing a wireway vs a J boxes? I need to install 6-4'' conduits going in and 6-4'' coming out. I want to use a24x24x96 wire way. ?

 

[MAC702]

One may care more about CCC (current-carrying conductors) and the other more about actual number of wires.

 

[RUBYDO]

are the requirements same the for sizing a wireway vs a J boxes? I need to install 6-4'' conduits going in and 6-4'' coming out. I want to use a24x24x96 wire way. ?

FYI - ALL SIZES ARE MINIMUM, ALL CODE REFERENCES ARE FROM THE 2017 NEC. WW means wireway. REMEMBER NEC 90.3
what is the difference between a WW and a pull/ splice box? not much. pull boxes, you get the square you need and thats it. a WW get the height and depth you need and you can add sections of length to it.

Hello, Yes. I'm late to your question, but hope this will help some folks in the future, or create great controversy. first a 24 x 24 is a very deep wireway or pull box, see 110.26(3) for set back of equipment.
376.23B sends you to 314.28 A1 and A2, for insulated condutors #4 or larger. , for the front to back depth, WW needs to be deep enough to handle the raceway. 4" conduit = 6" deep WW.

376.23A defelection is used for ALL size conductors. but how is deflection applied to a WW? if, in a WW, you install terminal bar, contactor, other mechanical lugs this is the minimum bending space required from whatever you use to the wall of the WW. and there are many other defelction scenarios. Here's an important one, raceways going out the back wall of the WW. an angle pull but NOT out the side or bottom, but the back wall. this will help you size the front to back depth of your WW. Table 312.6A

Are you using 4 inch conduit when you can use 3 inch? read 314.28E, (90.3) this says you can use the minimum size conduit for calculations, opposed to what you are actually using.

376.56A, huge confusion on this. IT'S NOT how you size a WW. it says that IF you are splicing, the splice and TAPS (LUG/BLOCK/ETC, everyone forgets to add these) , plus conductors, cannot exceed more than 75% of the area it is in.
376.56B, PDB's, follow manufacture install instructions. 376.56B2, again not how you size, it's too make sure you have the 75% area in that space. 376.56B3 wire bending space, this is a different table, 312.6B NOT A.

Remember 90.3, whether a feeder or supply side, don't forget to bond the metal WW. don't forget bushings on your connector fittings. 376.22A and B still apply to these larger conductors. 376.23B says WW used as pull boxes. then it sends you to 314.28A1 for straight pulls, and A2 for angel pulls, THIS includes U pulls and SPLICES. (90.3) tells us so.

Hope this is of some help. feel free to comment. if I'm in error on something let me know. can discuss.