[Fundamentals] concept of lightning protection zones (LPZ)
IEC lightning protection zone concept illustrated by 2 companies for WISPs installing antennas on rooftop of commercial or multi-tenant buildings. I think NFPA 780 recent updates use somewhat similar concept?
Bottom diagram show how/where the robust 10/350uS lightning surge protectors bond to the building grounding system. UL 1449 also has a special LPS SPD device class but only rated for 8/20uS waveform.
Please, no need to admire my Google skills ... I am still glowing from complimentary comments made by nevtxjustin and splitpair in recent threads.
Related concept illustrated by some Vietnamese cellular engineer. Cabinet is totally within the "rolling sphere" of protection of a well-grounded cellular tower.
The lightning surge protector for all cable entries into this cabinet still need 10/350uS rating but need to handle far less peak current.
Sadly outdoor-to-indoor or inter-site bonding has been a very contentious subject for WISPs and started the current arguments.
So here is my quick sketch of FAA recommendation based on NEC/NFPA and IEC. I think FAA recommended grounding wire with randomly spaced ground rods above any buried cable runs will also provide safety bonding between 2 remote sites without compromising lightning protection of either side.
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