Mike Short wrote:
> Use it for your image plane, not your lightning grounding system, and you
> will be fine. The #4 wire, etc from your tower to your SPG is the correct
> thing to do.
>
The actual NEC Art 810-21(d) requirement is that an AWG 6 copper or
larger bonding jumper must be used where separate electrodes are used.
(this requirement applies to interconnection of grounding electrodes..
not to other things that need to be grounded (e.g. antennas))
Same article only requires AWG10 for a satellite entrance cable to
building or structure grounding electrode system. If in a metal raceway
(conduit), both ends of the raceway have to be bonded to the conductor.
Other stuff not often brought up.. NEC requires an "antenna discharge
unit" for each cable coming into the structure, outside or inside, as
near as practicable to the entrance of the conductors, not near
combustible material, grounded with that AWG10 or larger wire, etc.
It's not clear (yet.. i'm researching it) whether an "antenna discharge
unit" can be a bulkhead coax feed through in a grounded plate.
Since lightning has come up, NEC says communications cables should be at
least 6 feet from lightning protection conductors (as always, "where
practicable")
ANd there's a whole raft of requirements about low voltage wiring
(<50V), depending on whether it's "Limited energy" or not. (that's the
whole Class 1,2,or3 low voltage thing), complicated by the fact that
many of the rules apply ONLY to wiring inside a structure, and it's up
to the inspector whether to allow something outside.
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