Cable tray used as a conduit support

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elec_eng

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EC used cable tray as a conduit and j-box support in a commercial installation. Per NEC 392.18(G) (2011), I don't think this is allowed but I just want to make sure.

To make this insallation worse, the conduit is attached to the bottom side of the cable tray with sinle hole conduit straps. They were just screwed in to the cable tray, which I believe are not listed cable clamp.

Am I reading the code correct?
 
You are correct, in a commercial establishment.

What EC used to attach conduit is moot... but you said he used one-hole conduit straps to attach conduit, then in the next sentence you question them as not being listed as cable clamps. I can't make the connection.
 
I don't see this a a real issue...you are specifically permitted to run the conduit in the tray, so what does it really hurt to run it on the bottom of the tray? Of course you have to look at the total load and what the tray is permitted to support, but you always have to do that.
 
don_resqcapt19 said:
I don't see this a a real issue...you are specifically permitted to run the conduit in the tray, so what does it really hurt to run it on the bottom of the tray? Of course you have to look at the total load and what the tray is permitted to support, but you always have to do that.
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392.18.(G) 2014 NEC
last sentence of first paragraph:
For raceways or cables running parallel to and attached to the bottom or side of a cable tray system, fastening and supporting shall be in accordance with the requirements of the appropriate raceway or cable article.
So it seems the installation is legal.
 
When someone mentions cable tray for a commercial installation, I usually think that it is installed for communications cables. If the cable tray was engineered to accommodate a certain loading of cable plus future expansion, it is not good engineering practice to add load to the tray. It may not be a code issue but it could be an issue for the engineer or the owner. That said a few small conduits fastened to a cable tray would not be problematic. Hopefully the screws used do not protrude into the tray surface where cables can be dragged across them.
 
Smart $ said:
The first three words of that paragraph: In industrial facilities...
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392.2 definition
cable tray system. A unit or assembly of units or sections and associated fittings forming a structural system used to securely fasten or support cables and raceways.
 
don_resqcapt19 said:
I don't see this a a real issue...you are specifically permitted to run the conduit in the tray, so what does it really hurt to run it on the bottom of thetray? Of course yt the what trpermitted to support, but you always have to do that.
Click to expand...

Then why 392.18(G) limits its use to "In industrial facilities"?
 
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