Wire bending space in conduit bodies

[conmgt]

Hi,

It occurred to me a while ago that just because you can fill a conduit with the largest conductor(s) allowed, that it doesn't mean that you can use an equal size conduit body because of wire bending requirements. For example, putting the largest single conductor allowed when running a EGC through EMT.
Looking at this Mulberry list, http://www.mulberrymetal.com/downloads/Conduit Body Dimensions.pdf , how do I determine wire bending space? Is it dimension E?

 

[kwired]

Hi,

It occurred to me a while ago that just because you can fill a conduit with the largest conductor(s) allowed, that it doesn't mean that you can use an equal size conduit body because of wire bending requirements. For example, putting the largest single conductor allowed when running a EGC through EMT.
Looking at this Mulberry list, http://www.mulberrymetal.com/downloads/Conduit Body Dimensions.pdf , how do I determine wire bending space? Is it dimension E?

Conduit bodies are marked with the largest allowed conductor and bending requirements are taken into consideration for this marking.

1/2 and 3/4 inch bodies usually have no marking, but conductors that fit into 1/2 and 3/4 raceways generally are too small to be an issue with bending space required.

 

[conmgt]

It would be nice if catalogs would give a list of allowed conductor sizes based on 1, 2, 3, 4 conductors.

 

[don_resqcapt19]

The only listings marked on the conduit body that I have ever seen are for 3 conductors. If your conductors are #4 and larger and you are installing more than 3, the conduit body must be sized per the rules in 314.28(A)(1) & (2) to be code compliant.

 

[conmgt]

The only listings marked on the conduit body that I have ever seen are for 3 conductors. If your conductors are #4 and larger and you are installing more than 3, the conduit body must be sized per the rules in 314.28(A)(1) & (2) to be code compliant.

Seems like for pretty much anything other than an LB or SLB, conduit bodies aren't going to work for #4 and larger. It makes me wonder how often is a 3" LL or LR usable.

 

[infinity]

As Don stated you must use the 6X and 8X sizing rules unless the conduit body is marked with a specific conductor size and amount. You can always increase the size of the conduit body to get larger conductors in it. If a conduit body larger than the trade conduit size is used then it must be supported.