Tie cables to threaded rod

[jeffrae]

Does anyone know of an ANSI or NFPA standard that allows you to tie low voltage cables to threaded rod? We were told that if you put a tie around the rod, then ran another tie through that one and around your cable, it would be legal. We have done this for years, and now we are getting called on it.

 

[egnlsn]

I don't know of a standard, but I usually just secure a tie-wrap to a threaded rod using another tie-wrap, with the cables going through the second one. That way, they aren't getting cut by the threads or pinched by the tie-wrap cutting into them.

 

[cadpoint]

I have to ask what type of low voltage wiring are you installing?

725.24 might answer your question. If the strapping of is associated to the equipment that it's for than yes, (if class 2) 300.11(B)(2). 300.11(B)(2) is mentioned again up in 725.143. The better thing is to install your own ceiling grid support wire from ceiling to grid and lash to that.

Recall that 725 uses 300 wiring methods only where exactly called out, and FPN 725.1, and 725.3.

All based on 2008 NFPA 70.

 

[jeffrae]

The cables we are installing are fire alarm cables. I know there are not many rules about the cable installation, but the contractor wants to, basically, see a picture of this type of installation proving that it is a listed means. I don't think I am going to find such a thing, but nothing I can find rules it out. They are basically saying that I can't prove that it is acceptable, so it is not.

 

[gadfly56]

The cables we are installing are fire alarm cables. I know there are not many rules about the cable installation, but the contractor wants to, basically, see a picture of this type of installation proving that it is a listed means. I don't think I am going to find such a thing, but nothing I can find rules it out. They are basically saying that I can't prove that it is acceptable, so it is not.

Caddy makes J-hooks and such for supporting data cable. You can even use threaded rod with some of their products.

 

[Gregg Harris]

The cables we are installing are fire alarm cables. I know there are not many rules about the cable installation, but the contractor wants to, basically, see a picture of this type of installation proving that it is a listed means. I don't think I am going to find such a thing, but nothing I can find rules it out. They are basically saying that I can't prove that it is acceptable, so it is not.

760.24 Mechanical Execution of Work. Fire alarm circuits shall be installed in a neat workmanlike manner. Cables and conductors installed exposed on the surface of ceilings and sidewalls shall be supported by the building structure in such a manner that the cable will not be damaged by normal building use. Such cables shall be supported by straps, staples, cable ties, hangers, or similar fittings designed and installed so as not to damage the cable. The installation shall also comply with 300.4(D).