Two questions on box capacity


Old 08-04-06, 01:01 PM
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Two questions on box capacity

1. The boxes I've purchased all have the capacity for both 14 guage and 12 guage wires stamped right on the box. (Carlon brand.) Is this with our without a receptacle/switch? If it is without, how much does the receptacle or switch reduce it by.

2. Do pigtails count? Say I have a box that says it can hold 9 twelve guage wires and I have three 12/2 cables coming into it. If I pigtail to the receptacle, have I exceeded the capacity?

Thanks much
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Old 08-04-06, 01:10 PM
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1) Box capacity is total. You must deduct for devices and internal metal clamps. The moulded in clamps in plastic boxes do not count.
Each device counts as two conductors, clamps count as one each.

2) Pigtails do NOT count in box fill.
Old 08-04-06, 01:10 PM
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I touched on that question here.

Read that and let me know what is not clear.
Old 08-04-06, 01:22 PM
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The only thing I would like to clarify is that when counting wires, you need to count each "end" in the box (not considering the grounds, they are a differrent animal) if you have 2-12/2 entering a box to make connections, you count each end (total of 4 ends). If the wire does not terminated in the box, it gets counted as 1 UNLESS it is looped the length of a normal termination (6 inches from entrance into box) then it is counted as 2 because it takes up the same space as as a termination.
Old 08-04-06, 01:30 PM
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Never mind

Never mind, I just found a good box-fill calculation resource.
Old 08-04-06, 01:32 PM
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Wow, you guys are quick. I didn't even get a chance to read your replies before I posted my "never mind." Sorry about that.

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