Supporting conduit bodies that support lighting fixtures

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Fomart

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If you are using conduit bodies to support high bay type lighting fixtures in a manufacturing area, and you are only going to support those conduit bodies from the conduits feeding them, do those conduits need to be Rigid steel or IMC? The contractor claims that the conduit bodies can be supported with EMT as long as the conduit between the conduit body and the lighting fixture is threaded IMC or Rigid.
 
Fomart said:
If you are using conduit bodies to support high bay type lighting fixtures in a manufacturing area, and you are only going to support those conduit bodies from the conduits feeding them, do those conduits need to be Rigid steel or IMC? The contractor claims that the conduit bodies can be supported with EMT as long as the conduit between the conduit body and the lighting fixture is threaded IMC or Rigid.
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I would have to read the article again, I don't have my code book with me. With exceptions a conduit body can support a fixture....if it has threaded hubs, supported by two raceways and the raceways are supported within 18" of fixture/box.
 
Beam Clamp, or Caddy beam clamp with threaded rod inside EMT attached
directly to light, sometimes I won't use a pipe if under five foot!

If you use Pipe support you can lash MC to it and or use it to secure other pipe
runs to.

The last part of the OP just sounds like total **, oh course that's JMO!
 
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Canton said:
I would have to read the article again, I don't have my code book with me. With exceptions a conduit body can support a fixture....if it has threaded hubs, supported by two raceways and the raceways are supported within 18" of fixture/box.
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Thats my understanding, but do those two raceways have to be rigid or IMC or can they be EMT?
 
Fulthrotl said:
would you hang a 40 lb fixture off two pieces of 1/2" emt with setscrew connectors?
30' up in the air? and then stand under it during an earthquake?

i wouldn't.
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Die cast fittings - no
Steel fittings - maybe

Seen heavy chandeliers, pendants, etc. at times with more questionable components.

I don't live in earthquake zone so no experience to answer for that part of question, but maybe would want an additional support cable or something like that even with RMC in an earthquake zone.
 
K8MHZ said:
The code says that the conduit must be threaded wrench tight into the hub. Not a fitting.

That pretty much eliminates EMT from being used, as it cannot be threaded at all, let alone wrench tight into a hub.
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You can thread EMT - just not with a NPT die for the same nominal size, probably not even a bolt thread for similar sized bolt as the threading die would cut all the way through the thin wall in most instances:happyyes:
 
kwired said:
You can thread EMT - just not with a NPT die for the same nominal size, probably not even a bolt thread for similar sized bolt as the threading die would cut all the way through the thin wall in most instances:happyyes:
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You could probably get a turn or two of tapered thread on the end of the EMT, but I agree that the full thread depth may be greater than the wall thickness.
 
K8MHZ said:
So what? 314.23 (E) and (F) specifies conduit. EMT is tubing, not conduit.
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Well then, are we allowed to thread other "conduits" like flexible metal conduit or liquid tight flexible metallic or non metallic conduit?

Just having a little fun with this here.
 
kwired said:
Well then, are we allowed to thread other "conduits" like flexible metal conduit or liquid tight flexible metallic or non metallic conduit?

Just having a little fun with this here.
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I understand. How much ink would be wasted if the NEC just came out and said that only RMC or IMC could be used?

The wording of the NEC doesn't prohibit FMC, but common sense and physical laws do. However, I see nothing in the NEC that prohibits threading PVC and using it to support a luminaire, but how long would that last when it got real hot like it does in most factories?
 
K8MHZ said:
I understand. How much ink would be wasted if the NEC just came out and said that only RMC or IMC could be used?
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None in the electronic versions, but they would use more data storage and would take more energy to display the extra characters when viewing it.:happyyes:
 
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