Is it because even though it is "NOT part of any full-time, current sourcing or current sinking device or system" it can cause the potential difference in the rare event the lightning strike cause both grounds to be used simultaneously?
Understood but doesn't that mean closely neighboring properties will already suffer this fate anyway? Our grounds aren't bonded with the neighbors ground which in some cases can be under 20-30ft apart.
Not so. I'm not going to sink a rod for a surge protector near an outdoor IP camera then run a wire 20 or 50 feet to bond that ground rod to my house's electrical system ground rod. That 20 to 50 foot conductor would guarantee a possible potential difference and therefore increase the likelihood of current travel!
It's because of the HIGH impedance due to the separate ground rods being 20 to 50 feet apart that lightning has NO reason to travel from one rod to the other rod if grounded to earth properly at the point of ESD arrest by the surge protection.
Again...not so, IMO.
And I think that's the best way to leave it: Say what you have to say and move on. There are plenty of other places where grounding is debated ad infinitum. I do want to mention one lightning related item. I have a couple of magnetic driveway sensors connected to the NVR's external event inputs, over a few hundred feet of wire each. I was uncomfortable connecting such a wire run directly to the NVR and ran it through optoisolator chips inside the house. Last spring, a nearby lightning hit took out one of the sensors and fried the optoisolator chips, but did no detectable damage to the NVR. In addition to replacing the fried sensor, I upgraded the optoisolators into sockets.
