Code for Running fire alarm cable Please Help

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MSSINC

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I have a situation where we installed a fire alarm system in a commercial building. We used bridle rings when we ran wire in with the direction of the truss beam. When we ran wire in the perpendicular to the truss bean we pulled the wire over the top of the truss bean in the waffle (ceiling pan) on top of the bean. The ciy inspector is claiming it is not properly supported. The wire is laying across 5" of the top of the beams. The inspector wants bridle rings or J hooks on everything.
Is it ok to run wire over the top of the truss beams? in the ceiling pan.
If so I will need to prove to him via code in NEC or National code.
 
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Not sure if it applies but 300.4(E) might be a problem. Having said that it seems that laying over the truss would provide support but the cables are secured.
 
Generally, the requirement is 760.24. It gives performance (not prescriptive) requirements for cable installation. It is essentially good workmanlike installation requirements.

Infinity, I was only able to see a requirement to 300.4(D) not (E)
 
ron said:
Infinity, I was only able to see a requirement to 300.4(D) not (E)
Click to expand...

300.4(E) is a new section in the 2008 NEC. Here is what that section says:

(E) Cables and Raceways Installed Under Roof Decking. A cable- or raceway-type wiring method, installed in exposed or concealed locations under metal-corrugated sheet roof decking, shall be installed and supported so the nearest outside surface of the cable or raceway is not less than 38 mm (1? in.) from the nearest surface of the roof decking.
FPN: Roof decking material is often repaired or replaced after the initial raceway or cabling and roofing installation and may be penetrated by the screws or other mechanical devices designed to provide ?hold down? strength of the waterproof membrane or roof insulating material.
Exception: Rigid metal conduit and intermediate metal conduit shall not be required to comply with 300.4(E).
Click to expand...

Chris
 
ron said:
Chris,
I agree that it is new, but there doesn't seem to be a reference in 760 telling you to go to 300.4(E), only (D)
Click to expand...

I see what you are saying. You are correct. 760.24 does not direct you to 300.4(E) just 300.4(D).

I will have to check the ROP's and see if this has been addressed for the 2011 code cycle.

Chris
 
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