Art. 300.11 (A) and (B)

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tobesure

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I find the intrepretations of this article vary from inspector to inspector and master to master electrician. What is your opinion of the following? (A) is a fire rated ceiling that seems to say that all electrical equipment, including light fixtures by the defininition of "equipment" is to have secure and separate support back to structure. That is to say provide separate support wires from the light fixture back to structure and all electrical equipment the same, unless it meets the exception.
(B) is a non fire rated ceiling yet seems to say the same thing, that all equipment will have secure and separate support back to structure. The exception is a little easier in that if the ceiling grid is installed per the manufacture's instructions, then you only apply Art. 410.36 which is luminaires being secured to the ceiling grid.

Although light fixtures is not mentioned in 300.11 (A) or (B) specifically, both exceptions referrer to "equipment" and by defination includes fixtures. What is your opinion? Are fixtures required to have support wires attached to the fixture and tied to the structure or not?
 
Going strickly from the NEC, if the ceiling grid system is designed to support the light fixtures then you can just attach the light fixtures to the grid in an approved manner. If the ceiling grid is not designed to support the light fixtures you would need to support the fixtures independ of the ceiling grid assembly.

Now, in addition to what the NEC requires, the building codes may also have requirements for independant support wires for light fixtures. This is typically a seismic requirement.

Chris
 
tobesure said:
I find the intrepretations of this article vary from inspector to inspector and master to master electrician. What is your opinion of the following? (A) is a fire rated ceiling that seems to say that all electrical equipment, including light fixtures by the defininition of "equipment" is to have secure and separate support back to structure. That is to say provide separate support wires from the light fixture back to structure and all electrical equipment the same, unless it meets the exception.
(B) is a non fire rated ceiling yet seems to say the same thing, that all equipment will have secure and separate support back to structure. The exception is a little easier in that if the ceiling grid is installed per the manufacture's instructions, then you only apply Art. 410.36 which is luminaires being secured to the ceiling grid.

Although light fixtures is not mentioned in 300.11 (A) or (B) specifically, both exceptions referrer to "equipment" and by defination includes fixtures. What is your opinion? Are fixtures required to have support wires attached to the fixture and tied to the structure or not?
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We have to define "wiring". That is what (A)(1) and (A)(2) say "shall not be secured to" the ceiling. They don't actually say equipment or fixtures. I think in this section, "wiring" means cables or conduit, and equipment in the exceptions means associated boxes, not the fixtures themselves.

If 410.36(B) 2008 requires the luminaires to be secured to the grid, then the "wiring" not to be secured in 300.11(A)(1 + 2) must be other than the fixtures.

Welcome to the forum. :)
 
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