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box size calculation using 314.28(A)(2)

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dalekenna2003

Electrical
Apr 28, 2011
1
Please help me interprete NEC 314.28(A)(2). What should be my minimum allowable box size with a removable cover on top, if I have 4" conduit of which the entry is at the bottom and located 4" away from the wall opposite of the exit conduit. The exit conduit is installed 3" away from the bottom of the box.

The code requires minimum size between walls, between the bottom and removable cover, and between the entry and exit conduits.

Thanks for any feedback.
 
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Depends on size of the wire: from 11/2" up to 12" [as per Table 312.6(A) column 1] for vertical dimension. Horizontal has to be 6*3=18".
But, as permitted in 314.28(A)(3) art.:
you may use smaller dimensions if the size and number of the cables is less than required in Table 1 chapter 9. But this has to be "permanently marked with, the maximum number and maximum size of conductors permitted."
 
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