Building mounted Security Cameras and Antennas and Chapter 8

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toddelec2

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We are working on a housing project where each 2 story building has multiple POE cameras and a single POE antenna mounted 12' AFG, the antennas used to connect building to building. All wiring is in conduit that terminates to an equipment cabinet that is grounded to the house panel feeding the cabinets. The antennas have a provision to be bonded to the raceway system separately from the CAT 6, which has been done. The buildings are old, and do not have Intersystem Bonding provisions.
I am unclear has to which parts of chapter 8 apply to this sort of installation, and what more I would need to do for grounding/bonding where the wiring is 100% in metal conduit?
 
As far as grounding, if the rack is grounded and bonded, and metal conduit is secured and bonded to it, then by default the conduit is grounded if properly installed and connectors used. Metal conduit is allowed to be an EGC and all metal attached to it would be grounded by means of it when properly attached (bonded) and as long as at some point the continuity is maintained to the main GEC at panel board. (Not speaking to if it is required.)
 
The titles of these two articles in Chapter 8 are a bit misleading.
810 is radio and television equipment (Antenna Systems)
820 is Community Antenna TV and Radio Distribution Systems (Coax)
I have installed 50+ antennas outside buildings for SCADA systems so worked thru the rules to understand them
Both are concerned with fire and lightning protection. Art 810 would apply to your antenna. If your antenna is outside it is exposed to lightning. With the antenna installed on RMC, a lightning strike will follow that RMC to your equipment.
What the code requires is a bonding conductor 810.21 run in a straight line, to a GE, see list in F 1 or 2, your grounding electrode must be connected to the structure GES. See 3 for no IBT.
I would not install the antenna on RMC, even though that looks nice. Hang it on the building, run a short length of carflex into the building, then bond the antenna to the GES. Or stub out and install a weather head and loop to antenna
Your POE cable should have a impulse suppressor in line, where the cable enters the building with a bonding conductor that connects to the bonding jumper that goes to the GES. See 805.90. I am not sure if 725 applies, but Don is seldom wrong. But good practice requires protection from lightning

The rules in 800, 805 are newer, and the rules in 810 and 820 date back many years. And its all about protecting outside wiring and equipment and wiring from lightning and high voltage

Most antennas I see, like 99%, on schools, fire stations, pump stations, dwelling units are not installed per code...I actually had a really great code change accepted to Art 810 about antenna grounding, where that article didn't have a reference to 250.8 meaning you could use a hose clamp for connection
 
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