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Hendrix

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Table c.1 Tells me that I can pull 4 350kcmil conductors through a 2.5 in. piece of emt. Can a one ought grounding conductor be included in that run ?
 
In Chapter 9 it says you can pull 4-350's through a 2 1/2 " EMT and that is what you can pull so if you want to include a 1/0 you would have to increase the conduit size. So my answer would be "no" to what you asked. That is assuming you mean you are pulling the 4-350's and want to include a 1/0.
 
The number of current carrying conductors has nothing to do with conduit size, for the fill. That is by cir. mil, so if it says you can pull 4-350s and that is what you intend to put in there you can not even if it is not a current carring conductor pull a 1/0. You would have to increase your conduit size. The number of current carrying conductors would just add to your derating, for instance if you had a 2" conduit and only put say 10 #12 current carring conductors that would be way under the fill but you would still have to derate due to the fact of having that many current carrying conductors.

Hope that helps.
 
wireguy8169 said:
In Chapter 9 it says you can pull 4-350's through a 2 1/2 " EMT and that is what you can pull so if you want to include a 1/0 you would have to increase the conduit size. So my answer would be "no" to what you asked. That is assuming you mean you are pulling the 4-350's and want to include a 1/0.
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What do you say, Lakee ?
 
wireguy8169 said:
In Chapter 9 it says you can pull 4-350's through a 2 1/2 " EMT and that is what you can pull so if you want to include a 1/0 you would have to increase the conduit size. So my answer would be "no" to what you asked. That is assuming you mean you are pulling the 4-350's and want to include a 1/0.
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Wireguy, look at Table 5 in chapter 9, 350 kcmil has an area of 0.5242 sq" and 1/0 has an area of 0.1855 sq " which equates to total area of 2.2823 sq" and Table 4 gives 2.5" EMT @ 40% an area of 2.343, so (4) 350 kcmil's and (1) 1/0 will be fine.

Roger
 
roger said:
Wireguy, look at Table 5 in chapter 9, 350 kcmil has an area of 0.5242 sq" and 1/0 has an area of 0.1855 sq " which equates to total area of 2.2823 sq" and Table 4 gives 2.5" EMT @ 40% an area of 2.343, so (4) 350 kcmil's and (1) 1/0 will be fine.

Roger
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Thank you, Roger
 
wireguy8169 said:
In Chapter 9 it says you can pull 4-350's through a 2 1/2 " EMT and that is what you can pull so if you want to include a 1/0 you would have to increase the conduit size. So my answer would be "no" to what you asked. That is assuming you mean you are pulling the 4-350's and want to include a 1/0.
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Actually the wire fill tables are in Annex C and not in Chapter 9. The information in Annex C is not part of the code.
 
Thanks, I ment to put Anexx C just was looking at chapter 9 on my index. Hmm never knew that the anexxs were not part of the code, so what is the purpose of them?

Hendrix, sorry gave you wrong info....and thanks for the corrections
 
Which table to use makes a big difference some times, If I remember correctly, the table used when all wires are the same size, 3/4" conduit is allowed to have 4-#6 thhn wires in it. But if you have different size wires, the other table will not allow 3-#6, and 1-#10 in the same size conduit. Of course this was several code editions ago, and I have not checked it lately.
 
wireguy8169 said:
Hmm never knew that the anexxs were not part of the code, so what is the purpose of them?
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We can often use them to avoid doing the math. If you are using all conductors the same size, it would be safe to use the tables. Or, for example, if you want to pull (3) 350's and a 1/0, through a 2 1/2 inch emt, you wouldn't have to do the math, because the table say (4) 350's will work, so (3) 350's and a 1/0 will certainly work. Sometimes though, as this thread shows, if you want to be sure, you just have to do the math.
 
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