Box Size

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mstrlucky74

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I have (4) 6? conduits entering one side and exiting on theopposite wall. (2) spare and (2) w/ 3#500 & 1#4/0 each. What size box wouldI need?
Thanks.
 
mstrlucky74 said:
I have (4) 6? conduits entering one side and exiting on theopposite wall. (2) spare and (2) w/ 3#500 & 1#4/0 each. What size box wouldI need?
Thanks.
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Code section 314 Even without the code book this one is easy. opposite wall is 8 times the diameter of the largest conduit, BUT there is an exception that allows you to use the nominal conduit size that the conductors can fit in if you use oversized conduit. So for current wires I believe that 3 #500 and a 4/0 can fit in a 3" conduit so 24 inch can.
 
Strathead said:
Code section 314 Even without the code book this one is easy. opposite wall is 8 times the diameter of the largest conduit, BUT there is an exception that allows you to use the nominal conduit size that the conductors can fit in if you use oversized conduit. So for current wires I believe that 3 #500 and a 4/0 can fit in a 3" conduit so 24 inch can.
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There is no exception that I am aware of that would permit that. If you are talking about the last paragraph in 314.28(A)(2), that is used to find the required box size where a cable wiring method is used. You can't use that if a raceway has been installed.
 
Don't you need to figure spacing for other (3) 6" conduits on top of the 8x6?


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If we size it... next time you need one sized you will come here :)
Use the link jumper gave you in Post #2 and tell us what size you come up with and we can check your dimensions.
 
Don, I was thinking of 314.28 (A)3 mstrlucky and actiondave, when the conduits enter one end and go out the other, you don't have to figure anything for the additional conduits. For everyone especially Don. It has been a few years since I researched this and I thought there used to be something about wire smaller than the max fill of the conduit. Since I can't find it and Don corrected me, riddle me this. A 4 11/16 with 1 1/4" eccentric knockouts in it. In no case does that box comply with 314.28 (A) 1 or 2. The rule I was thinking of that I may have dreamed was one that would allow this. Please enlighten me.
 
Strathead said:
A 4 11/16 with 1 1/4" eccentric knockouts in it. In no case does that box comply with 314.28 (A) 1 or 2. The rule I was thinking of that I may have dreamed was one that would allow this. Please enlighten me.
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You can use that box with an 1.25" raceway and conductors #6 and smaller.
 
Strathead said:
Per which code section that I can't find?
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Per 314.28(A).
For conductors smaller than #4, the dimension of the box is not relevant. For #6 and smaller the determining factor is cubic inches as shown in 314.16.
 
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