Do I bond the LPS for a concrete CCTV pole to the cabinet ground array if the pole is 200 feet away

Cjmccarthy

Member
Location
Florida
Occupation
Project Coordinator FDOT
This is an FDOT project involving a controller cabinet housing all equipment, including a ground array bonded to the power source ground rod. A concrete CCTV pole is located approximately 200 feet away, equipped with an aerial lightning protection system (LPS) connected to its own ground array.

Given that the only connection between the cabinet and the CCTV pole is a POE Cat6 cable, we would like to confirm whether it is necessary to bond the CCTV pole's ground array to the cabinet’s ground array, despite the distance or should it be isolated?

Your guidance on whether bonding is required in this configuration would be appreciated.
 
My _guess_ as a non-expert in the field of lightning protection is that having two LPS systems 200 feet apart connected by a signal wire will be a recipe for disaster.

Earth currents caused by nearby lighting strikes will enter one ground array and use the wires as a path to the other ground array.

I think you would want to ensure that both ground grids are set up to limit any potential difference between them.

But like I said, this is not my field of study. I'd appreciate it if you could share any professional information you receive.

Jonathan
 
(Also not a lightning protection expert)

Remember that twisted-pair Ethernet is galvanically/electrically isolated, and most PoE cameras do not connect any of the power conductors to the case, so I wouldn't be concerned, much, from that angle. Unless the cable is buried, you'd want an arrestor at the pole and at the source; might anyway, they're relatively cheap insurance.

I'd expect that the pole and any lightning terminal is stoutly bonded to a rod under the pole (array? why?), but if it's a metal pole the lightning would probably take the anchor bolts as the main path anyway.
 
This is an FDOT project involving a controller cabinet housing all equipment, including a ground array bonded to the power source ground rod. A concrete CCTV pole is located approximately 200 feet away, equipped with an aerial lightning protection system (LPS) connected to its own ground array.

Given that the only connection between the cabinet and the CCTV pole is a POE Cat6 cable, we would like to confirm whether it is necessary to bond the CCTV pole's ground array to the cabinet’s ground array, despite the distance or should it be isolated?

Your guidance on whether bonding is required in this configuration would be appreciated.
I would not even consider a POE cable for this application...it would need power and fiber if I was doing it.
 
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