Supporting at Bends

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Alwayslearningelec

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Came across this in spec. Is this code to support a particular distance on each side of bend? Thanks.

Support exposed conduits by use of hangers, clamps, or clips. Support conduits on
each side of bends and on spacing not to exceed NEC requirements.
 
That's a new one. NEC has no requirement for bends but I can see an issue with large elbows especially if the supports are 10' apart and end up right next to a couplings.
 
infinity said:
That's a new one. NEC has no requirement for bends but I can see an issue with large elbows especially if the supports are 10' apart and end up right next to a couplings.
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I think it is a matter of craftsmanship. I like to support both ends of a conduit elbow if I can. I would not be able to do that if the job spec said I was not to exceed NEC requirements.
 
K8MHZ said:
Not to exceed NEC requirments. I don't think I have ever seen such a request.

I don't think you will find an NEC requirement regarding special support for bends in conduit.
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I think what the specification means, is that the spacing between supports is not to be a distance that exceeds the distance specified in the applicable section of the NEC. The specification isn't forbidding you from supporting at 8 ft O.C., where the NEC support interval is 10 ft. Something you would have to do, if structural member spacing intervals don't routinely add up to 10 ft. But it would disallow a 12 ft O.C. support interval where the NEC requires a 10 ft max support interval. That one goes without saying.

Where bends are encountered, the NEC doesn't provide guidance on how this impacts the support intervals. By omission, the 10 ft interval would continue along the path of the centerline arc length, as if it were a straight section. This leads to lop-sided possibilities, where Support 1 could be just 1 ft from the intersection point of the two centerlines, and Support 2 could be 8 ft from this point. This doesn't intuitively feel correct, yet it meets the NEC wording. It is understandable that job specs would require a support within 2 or 3 ft of a bend, or a support at the midway point of the bend itself, to ensure extra stability.
 
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