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Calculate conductor equivalents to prevent box fill violations
Your statement, "You can use Table 314.16(A) only if the box contains no switches, receptacles, luminaire studs, luminaire hickeys, internal cable clamps, or equipment-grounding conductors. This is rarely the case." is misleading. The only time you will not be using any of the figures in table 314.16a is when the box is unmarked or not of the size in Table 314.16a.
Table 314.16(A) is for metal boxes. Section 314.16(A)(1) permits us to use that table when the cubic inch capacity is not marked on the box by the manufacturer.
If the manufacturer has marked the cubic inch capacity on the box and it is greater than that which is shown in Table 314.16(A), then you can calculate based on manufacturer's sizing per 314.16(A)(2).
So yes, Table 314.16(A) would not include any devices, switches, receptacles or utilization equipment. You will have to refer to 314.16(B)(1) thru (5) for making allowances for devices, etc.
Notice that this table only includes sizes 18 AWG through 6 AWG.
8x8x4 box, no listed volume. Is there an 80% conductor rule that applies to the allowable box fill?
What do I do if on the test it asks for two 12 AWG and four 10 AWG? It doesn't say two 12/3 or four 10/2.
are there NEC requirements for cables going thru a fitting at a bulkhead into a PEC bldg. (myers hub, etc.)? How do you calc fill, or "...as long as it fits thru...).
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