Grounding question

Welcome to the forum Vaughn.

Do you have lightning strike possibilities in your area?

What is the soil like (rock, dry/sandy, etc.)?

-Bill

Grounding is sort of addressing two different issues that have two different "physics" behind how they work.

The first is the classic 120/240 VAC 60 Hz (and 12/24/48 VDC) grounding issues. More or less, your ground is a single rod near the main panel and is usually tied to a cold water pipe to keep things at "ground potential". If there is a short circuit (120 VAC to electrical box, or metal faucet, etc.), the green wire ground connection (and tied to AC neutral and DC battery bus negative) provides a current path to trip the breaker or fuse (i.e., an unground sink garbage disposal with a short to 120 VAC hot wire, would be an electrocution hazard).

The AC main panel ground and neutral to ground bond (in one location) is then tied to a ground rod and water pipe. The ground rod does not really have good enough electrical connection to (for example) trip a 120 VAC 15 amp breaker. The maximum resistance of 25 Ohms from ground rod to earth only carries (120 VAC / 25 Ohms 4.8 amps... The ground rod is needed to reduce the possibilities of galvanic corrosion, and provide a ground references for some applications (some florescent lamps need a grounded metal chassis to start reliably, etc.).

The other major need for ground rods is for lighting control. For those, ground rods need to be installed close to where the "thing" being protected is mounted. I.e., a ground rod for the main electric panel. Another ground rod for the solar array (if not close to the main panel), etc. More or less, lighting is a "radio frequency" current (albeit a very low frequency), and will not follow a 6 AWG cable for more than 10 feet, or take a right angle bend, without jumping to something else that provides a lower impedance to ground (impedance being the key term here-The distributed inductance and capacitance of the cabling and other physical issues that change impedance--such as wide sweeping radius vs sharp 90 degree turn in wiring).

And because the ground rods and grounding also needs to address the 120/240 VAC and VDC safety ground requirements--Tying all separate ground rods together with a 6 AWG cable (home size power system) supports that short circuit/trip breaker function that is needed.

Other issues like running solar panel grounds and DC wiring down the roof and on the outside wall to ground rod exterior to foundation (for grounding ing) and surge suppressors where the DC lines enter the home (you want to divert lightning energy "outside" of the home envelope).

Any way, a very complex subject. Here are some links with more information:
-Bill