Confused with table C.8(A) NEC

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hidroela

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I am calculating max number of wires in conduits and came across this
From table 5 in chapter 9 THHN No.6 conductor area is 0.0507 in2
And from table 4 article 344 6?? RMC fill area at 40% is 11.663 in2
Now 11.633 / 0.0507 = 230.039 in2 give me the max number of wires in that raceway at or bellow 40%
But if I try to use table C.8(A) would show a different value of 258
What I am missing

Best regards
HP :D
 
Table 8(A) is for compact conductors, see Table 8

(missed your Post #2)

Hopefully this is a "test" question and not an actual job.
 
augie47 said:
Table 8(A) is for compact conductors, see Table 8

(missed your Post #2)

Hopefully this is a "test" question and not an actual job.
Click to expand...

Aren't all conductors compact nowadays?
Have you ever compared a THW from 20 years ago with the THW that we have today?(which is also THHN......and all others)
 
Strife said:
Aren't all conductors compact nowadays?
Have you ever compared a THW from 20 years ago with the THW that we have today?(which is also THHN......and all others)
Click to expand...
No. The compacting is in the shape of the strands that make up the conductors and has nothing to do with the insulation type. The stands in a compact strand conductor are not round like they are in standard conductors.
 
don_resqcapt19 said:
No. The compacting is in the shape of the strands that make up the conductors and has nothing to do with the insulation type. The stands in a compact strand conductor are not round like they are in standard conductors.
Click to expand...

Here is a pic to add to what you said.

701ecmALUMpic1.jpg
 
My question is, are these avalable? I want to parallel 350 Kcmil copper conductors to get to 600 amps, for a residential service. There for I could use 2" IMC instead of 2 1/2" IMC. Cheaper and I have a threader.
Thanks
MIke
 
So what are the conductors called that look like a rubber cord. I have seen 3/0 copper conductors that look like there are a 100+ strands. The wire is in the cutler hammer 400 amp combo meter base panel. I thought that was compact conductors.
 
Dennis Alwon said:
So what are the conductors called that look like a rubber cord. I have seen 3/0 copper conductors that look like there are a 100+ strands. The wire is in the cutler hammer 400 amp combo meter base panel. I thought that was compact conductors.
Click to expand...

You might be referencing DLO Locomotive Cable. A 4/0 DLO has 551 starnds. Most cables also carry a RHW listing.

Obviously grat flexibility but requires unique termination .
 
augie47 said:
You might be referencing DLO Locomotive Cable. A 4/0 DLO has 551 starnds. Most cables also carry a RHW listing.

Obviously grat flexibility but requires unique termination .
Click to expand...
Thanks Gus-- Maybe that was what it was in the panel. Must be nice to pull as it is incredible flexible. Since it was part of the oem I suspect the terminations were appropriate.
 
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