300 mcm how many in conduit per nec code

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Dennis Alwon

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Well, that was the most convoluted method of getting the right answer that I have ever done. First I used the wrong table. Then I used the wrong wire then I started to use Table 5A till I saw your post, then I final did something correctly..... Geez:grin:
 

480sparky

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Iowegia
Well, that was the most convoluted method of getting the right answer that I have ever done. First I used the wrong table. Then I used the wrong wire then I started to use Table 5A till I saw your post, then I final did something correctly..... Geez:grin:


Meethinks that was the purpose of the thread. :cool:
 

Volta

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Location
Columbus, Ohio
It's XHHW-2 in the OP, not XHHW. That's why I used a manufacturer's spec.
Yup, works for me.
So I'm not smarter than a 5th grader. 1.878 / 0.3904 = 4.48.
Are too!! :grin:
Not let's let the other shoe hit the floor.:roll:



I gotta learn to push the right buttons on my calculator.

Got it..... but it is still 4 wires. and its 4.8

Pick up those shoes! Check out Note 7, Ch. 9.

5 wires! :grin:
 

Dennis Alwon

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Ken--Did you notice the asterisk at the end of Annex C first page.

*Where this table is used in conjunction with Tables C.1 through C.12, the conductors installed must be of the compact type.

Interesting...
 

480sparky

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Location
Iowegia
Ken--Did you notice the asterisk at the end of Annex C first page.



Interesting...


No, I stopped when I saw they were for information only and not part of the NEC.

.............Pick up those shoes! Check out Note 7, Ch. 9.

5 wires! :grin:

So do I get to wager my $1,000,000 for the Final Test, and multiply it by 10 if I get it right?

(Man, I could really use $10mil right now!)
 

Dennis Alwon

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Retired Electrical Contractor
Well here is another issue. Unless you use the manufacturer that Ken looked up you better make sure what their dimensions are. Everywhere in Table 5 xhhw and xhhw-2 are given as the same dimension so if you go back to Table 5A then you would neec to use .4015

1.878/.04015 = 4.7 rounded up.

You are right on the edge of this so I don't know what I would do.
 

Volta

Senior Member
Location
Columbus, Ohio
Well here is another issue. Unless you use the manufacturer that Ken looked up you better make sure what their dimensions are. Everywhere in Table 5 xhhw and xhhw-2 are given as the same dimension so if you go back to Table 5A then you would neec to use .4015

1.878/.04015 = 4.7 rounded up.

You are right on the edge of this so I don't know what I would do.

Regular stranding in Table 5, compact is 5A. But XHHW-2 is not listed, thus 480 bringing in manufacturer's info.
 

Dennis Alwon

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Retired Electrical Contractor
My point was that all the other tables use xhhw and xhhw-2 as the same. Why would it change for compact conductors. The insulation appears to be the same. Just a thought. Why is it not listed-- I don't know.

Give the money to Ken-- he apparently needs it. :grin:
 

ohmhead

Senior Member
Location
ORLANDO FLA
Well i also say pvc sch 40 as 4 total with no ground if you had 3 hots and a neutral and a ground wire .
With xhhw -2 they dont show the - 2 in the table 5 - A compact i think because its just a rating of insulation temp wise and is not changing anything diameter wise .

Most compact wire is smaller in diameter alu compact wire then just regular conductors . But we had a new job and we looked at this issue of diameter to different type of wire .

If we just pull in Simpull wire for all our feds with no soap its colored and less time to pull thats great .

But the biggest thing about Simpull that we found its diameter is smaller then any other wire in the nec tables so now we can install 4 conductors with a ground in a 2 1/2 inch conduit and where going with Thwn -2 Simpull aluma flex its smaller in size then Xhhw-2 or any of the compact conductors shown in table 5 -a just thought we pass that on to all the folks here . Simpull 300 mcm is only .706 mil in diameter
 
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