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Is there a reason an electrical inspector or building inspector could fail an inspection? One of my co-workers thinks it's acceptable to use All-Thread holding up HVAC and electrical equipment in the ceiling as a pull point for AV and data cable at 90-degrees. I think it's an egregious practice, but can't think of why specifically off the top of my head. Prefer references and inspector experiences.

  • Manufacturer's Minimum bend radius?
  • Likelihood of damage the cable sheathing, internal insulation and copper wire from sharp edges?
  • NFPA 70 National Electric Code (NEC)
  • Building Industry Consulting Service International, Inc. (BICSI) Telecommunications Distribution Methods Manual (TDMM)?
  • ANSI/TIA-568.1-D Commercial Building Telecommunications Cabling Standard?
  • National Electrical Contractors Association NECA 1 Standard for Good Workmanship in Electrical Construction?
manassehkatz-Moving 2 Codidact
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Jules Bartow
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    How hard to sheath the threaded rod? Or fit a guide using the locked nut method? – mckenzm Oct 10 '18 at 06:18
  • mckenzm,
    Good point. Sheathing rod with split loom pretty easy. Can also batwing a J-hook. Or run wire a different route altogether.

    Locked Nut Method --what/how does that work? Never heard of it.

     – Jules Bartow Oct 29 '18 at 02:46

2 Answers2

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This is a bad idea right off the bat because the threads on threaded rod are usually pretty sharp and could very well damage the cable.

Pulling around a fixed object rather than a pully or sheave that rotates is never a good idea.

The TIA/EIA standards specify bend radii, and sharp bends violate telecom standards, manufacturer's recommendations, etc., but usually does not violate the NEC which is what the inspector enforces. In most cases the inspector and the NEC don't care if you compromise the performance of your cable as long as you don't create a safety hazard. The other standards may be good practices, and may be contractual obligations, but they are not the inspector's concern.

batsplatsterson
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In my experience, Cat 3 (I've been doing this a while)/5/5e cable is quite forgiving. As long as you don't nick the outside of the cable (and sometimes even then), and terminate the ends properly, it works just fine. I've pulled through all kinds of crazy stuff in ceilings and walls. Sometimes it takes a while, but if you can get it through, it works.

That being said, the final location of the cables does matter - e.g., don't use electrical conduit that has live wires in it to pull ethernet cable. I did have one time running ethernet cables through an office under construction where the inspector complained (and I fixed) because the cables ran through the sharp pre-punched holes in a wall of metal studs without any protection (almost all my cabling jobs are after the walls are already up so this isn't an issue). I don't know if that was technically a problem or not, but I put in something like plastic bushings to fix it.

It is also very important to use the right type of cable. I use plenum-rated cable most of the time, whether necessary or not, to avoid problems. Plenum cable explanation

manassehkatz-Moving 2 Codidact
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    Plenum cable is more expensive than plain PVC or Riser, but then you can run it above ceiling grids that are used for return air. – Jules Bartow Oct 29 '18 at 02:48