You should have one ground rod for every joule of energy you charger has, spaced 10′ apart and connected.
You should have as many lightning rods +1 as ground rods.
The lightning arrestor/rod field should be where the charger attaches to the fence.
The ground system should at least 150′ away from the charger/lightning rod system.
Switching to a powerflex or fiberglass post will solve many issues with shorts, I glad I have. I had to walk my fence weekly repairing shorts/broken plastic insulators. Now I dont. I have had my blind horse run straight through (I was standing there when it happened) my powerflex/high tensile fence with no injury to the horse, nor to the fence because every thing could stretch and move instead of being ridged and like a knife.
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