Lightning Conductor Ran thru Service Equipment??

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jclint07

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Engineer wants aluminum cupola, on top of new building, "grounded to provide lightning protection." During phone conversation, he was concerned about a direct lightning strike to this piece of aluminum equipment on roof. Initially, this bare 3/0 copper conductor was supposed to be ran in pvc conduit, completely independent of all other conductors, and ran to 3 seperate ground rods, then bonded to the building steel, which is being used as an electrode.

Electrical contractor can not route conductor independently, due to building already being completed. So electrician's solution was to run conductor in existing, interior metal raceway, through service equipment pullbox, then through service CT metering cabinet, then finally down to ground rods. He commented it was his only option to go from point A to point B.

#1) So what does this 3/0 copper conductor qualify as?? Not a GEC, but it's connected to grounding electrode system.
#2) Isn't routed through service raceways and CT metering equipment the last place you would want a "lightning conductor"??
 
jclint07 said:
Engineer wants aluminum cupola, on top of new building, "grounded to provide lightning protection." During phone conversation, he was concerned about a direct lightning strike to this piece of aluminum equipment on roof. Initially, this bare 3/0 copper conductor was supposed to be ran in pvc conduit, completely independent of all other conductors, and ran to 3 seperate ground rods, then bonded to the building steel, which is being used as an electrode.

Electrical contractor can not route conductor independently, due to building already being completed. So electrician's solution was to run conductor in existing, interior metal raceway, through service equipment pullbox, then through service CT metering cabinet, then finally down to ground rods. He commented it was his only option to go from point A to point B.

#1) So what does this 3/0 copper conductor qualify as?? Not a GEC, but it's connected to grounding electrode system.
#2) Isn't routed through service raceways and CT metering equipment the last place you would want a "lightning conductor"??
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250.106 FPN #2 states that spacing from the lighting protection conductors may be required in accordance to NFPA 780-2008, "Standard for the Installtion of Lightning Protection Systems".
 
I don't believe I would want my lightning conductor run twith my other conductors. 230.7 allows grounding conductors and bonding jumpers in the same raceway with service conductors. Not sure what to call this lightning conductor other than a grounding conductor. Not sure the NEC was thinking Lightning wires when this was written
 
Dennis Alwon said:
I don't believe I would want my lightning conductor run twith my other conductors. 230.7 allows grounding conductors and bonding jumpers in the same raceway with service conductors. Not sure what to call this lightning conductor other than a grounding conductor. Not sure the NEC was thinking Lightning wires when this was written
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But when they wrote 250.106 Lightning Protection Systems they were.
 
K8MHZ said:
But when they wrote 250.106 Lightning Protection Systems they were.
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I was not disagreeing with you. Definitely something to be wary about, I just wanted to point out that section and not have someone justify it using that art.
 
Thank gentlemen. Waiting on our fire marshal to bring me over his copy of the NFPA 780. Electrician is already in process of rerouting conductor (whatever it qualifies as) by itself, down to grounding electrode. He said boring thru concrete & rerouting was quicker than waiting on response from the engineer.:D
 
jclint07 said:
Thank gentlemen. Waiting on our fire marshal to bring me over his copy of the NFPA 780. Electrician is already in process of rerouting conductor (whatever it qualifies as) by itself, down to grounding electrode. He said boring thru concrete & rerouting was quicker than waiting on response from the engineer.:D
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Here is a free download for the 2004 version:

http://uqu.edu.sa/files2/tiny_mce/p...4310333/Appendix_-_NFPA_Standard_780_2004.pdf

It still costs money for the 2008 issue.
 
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