Min. ground conductor size for lightning protection system

[anbm]

For lighting protection system, is there a code requirement for min. conductor size that connect all air terminals, equipment on roof, downlead conductor, rods and ground loop? Thanks!

 

[anbm]

Previous message... I mean " lightning " protection system (NFPA-780 relates) not lighting. Thanks!

 

[bob]

For lighting protection system, is there a code requirement for min. conductor size that connect all air terminals, equipment on roof, downlead conductor, rods and ground loop? Thanks!

You need to contact some of mfg for information or the National Ltg Protection Institute. The NEC won't help you much.

 

[bphgravity]

YES. There are minimum conductor size requirements outlined in the NFPA 780 and as identified in the UL96 and 96A standards.

 

[ZoneOfProtection]

Per NFPA 780-2008
Copper Class I materials
Main conductor, solid strip
Thickness 0.051 in.
Cross section area 57,400 cir. mils

Aluminum Class I materials
Thickness 0.064 in.
Cross section area 98,600 cir. mils

Class II = Structures exceeding 75' in height
Copper Class II materials
Main conductor, solid strip
Thickness 0.064 in.
Cross section area 115,000 cir. mils

Aluminum Class II materials
Main conductor, solid strip
Thickness 0.1026 in.
Cross section area 192,000 cir. mils