1 awg cu in???

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yankeeman411

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nj
Anyone know what the cu in on a 1 awg is. Need to figure out if i can put 4 1 awgs and a # 6 ground in a 2 inch lb that is listed for 3 2/0s or i believe 70 cu in?
 

infinity

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Location
New Jersey
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Journeyman Electrician
Is the 2" conduit body opening 6X the trade size of the raceway? If not then you cannot exceed what is written on the inside of the conduit body which is listed for 3 conductors. The cu inch amount is not relevant.
 

don_resqcapt19

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Illinois
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retired electrician
I think it would be fine, but under the current wording of the code, there is no permitted calculation to say that combination of wires is permitted. As Rob says the volume of the conductor has no meaning for the application of this section.

Even though the code wording does not permit it, the conduit body manufacture will have a table the lists size combinations that are not marked on the fitting, and I am sure your combination would be permitted by that listing, but the code does say you can do that.

I submitted a public input to say that you can use the published combinations, so maybe this issue will be fixed for the 2017 code.
 

infinity

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New Jersey
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Journeyman Electrician
I submitted a public input to say that you can use the published combinations, so maybe this issue will be fixed for the 2017 code.

I hope so since this is such a common violation. I think that it would be nice if the code allowed for some sort of calculation as well.
 

yankeeman411

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Location
nj
It seems silly cause it lists the 3 3/0s and a cu in capacity. Its not 6x the trade size either. From hole to hole its probably 6"
 

don_resqcapt19

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Illinois
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retired electrician
It seems silly cause it lists the 3 3/0s and a cu in capacity. Its not 6x the trade size either. From hole to hole its probably 6"
The volume is listed so you can use the fitting with conductors smaller than #4. The box fill rules in 314.16 apply when using the fitting with conductors smaller than #4.
The 6x applies when using the fitting with conductors #4 and larger. The marking that permits the use of three 3/0s is provided for in 314.28(A)(3). Please note that only the last paragraph of this section applies to standard conduit bodies.

The first part that talks about conduit bodies with a radius that complies with minimum bending radius for the same trade size conduit as shown in Chapter 9, Table 1.
These are not standard conduit bodies. This type is what the first part of the code section is talking about.
 
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