xguard
Senior Member
- Location
- Baton Rouge, LA
Violation? 314.23 F or Luminiare hung by conduit (with "reinforcement")
- Thread starter xguard
- Start date
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xguard
Senior Member
- Location
- Baton Rouge, LA
There is roughly 5 feet of conduit extending beyond the last horizontal unistrut support. Can I count the 45 degree support as it's only connected back to the conduit itself?
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
It is connected to the conduit very very close to where the conduit is connected to the unistrut. It is a perfectly adequate support by triangulation for the first part of the conduit.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
RMC can support a fixture so what might be the problem?
K8MHZ
Senior Member
- Occupation
- Electrician
texie
Senior Member
- Location
- Fort Collins, Colorado
- Occupation
- Electrician, Contractor, Inspector
JDB3
Senior Member
- Location
- San Antonio, Texas
I'm thinking that may be a spring nut and a separate conduit hanger.
I believe that we use-to call them pain-hangers. But they would do the trick!
I believe that we use-to call them pain-hangers. But they would do the trick!
Carultch
Senior Member
- Location
- Massachusetts
Or it use parallel routing strut straps like this:
http://www.unistrut.us/images_pages/P1563.png
I think what they really did, is bend the gripping tabs of a standard strap outward with a vice grip, so that they reach behind and grab the strut folds. This probably only works with 1/2" conduit, as its OD is about the same as the inner width of a strut.
I'm concerned about the 45 degree reinforcements, because it looks like the strut sidewalls were slit in order to bend it. So only the bent bottom surface of the strut is carrying the load. The sidewalls provide its strength in bending. The strut product was altered in a manner that compromises its structural integrity.
Last edited:
Carultch
Senior Member
- Location
- Massachusetts
Is RMC allowed to support RMC that is supporting a fixture? That is the crux of the issue.
As I understand it, when RMC is used as a raceway, it is not allowed to support anything unless the NEC specifically allows it. Such as some lighting fixtures.
I disagree. Anybody with an ounce of rationale can tell the strut will hold that fixture.
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- Location
- New Jersey
- Occupation
- Journeyman Electrician
What code section would prohibit using RMC as a raceway and as the support for a light fixture? Other raceway types are explicitly prohibited from being use as such, for example EMT in 358.12(5).
Carultch
Senior Member
- Location
- Massachusetts
Maybe I should rephrase that. The issue is that this installation has section 1 of RMC supporting section 2 of RMC. Section 2 of RMC is then supporting the fixture.
It is OK for section 2 to support the fixture, but is it OK for section 1 to support section 2?
Realistically, the loads are probably so low that it isn't an issue that actually causes real life hazards, but it is the concept that matters.
speak2jenni
Member
- Location
- Nyc
The strut is absolutely structurally compromised. It is cut and would only require time and vibration and weather to cause it to fail, all of which are in plenty in outside conditions. If this installation had been made using 45° strut angle 3 or 5 hole straps, i would agree, but this installation is using the strut inappropriately. Yes, it will hold... For a while. But i wouldn't use that for any type of permanent installation.
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mivey
Senior Member
Rationally, at the very least, I see the creation of a rust and stress fracture point on the diagonal part that was cut and bent.
Everything we put outside has the potential to rust. Stress fracture? Have you worked with strut before or do you just spec it?
- Location
- Massachusetts
Yes, and most of those things we put outside have coating to keep them from rusting. The cut removed that protection at the cuts and it will rust immediately.
That said,I would not have installed the struts, that fixture would be fine without the extra ugly brace.
K8MHZ
Senior Member
- Occupation
- Electrician
That's the same thing I was thinking. I have seen lights like this for years (less the brace). They used to be real popular at gas stations.
RMC is tough stuff.
Almost every piece of strut that you see outside has a least one field cut edge. We put a galvanized coating on these edges but I doubt the rest of the world does. It probably depends where you're at it concerning how fast it would rust. I've seen installations many years old without any evidence of rusting.
I agree the pipe the doesn't need that bracket but I wouldn't for one second try to say it's hindering in any way.
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