Hello everyone, i building my first ground mount and have two questions about the grounding rod.
1st i see you can buy either solid copper or copper clad/plated, which are the best to use ?
2nd i only have around 10" of soil then i'm down to solid natural rock so all my post holes have been dug out using a jack hammer, holes are 24" x 24" x 36"x depth, will i be ok to drop two rods in the post holes one either side of the array and concrete them in, it may be possible for me to hammer a small hole in the bottom the length of the hammer chisel 14" and get the rod down further but my main concern was will the grounding work if the rod/s are encased in concrete.
Take care
john
John I see you have not returned as of yet. Let me offer you this.
For the solar panels the only purpose a Earth Ground serves is for lightning protection and touch potential. Otherwise it has no other function. So if lightning strikes the panels, there is a planned path to earth to discharge, or prevent someone from being shocked if they touch the structure. The panels would work without any earth ground just fine. If the panels are on the roof of your house poses a significant threat from Lightning. However on a Ground Mount the risk are significantly lower. So what is important is you follow minimum electrical codes.
OK you are stuck or perhaps trapped yourself in a Ground Rod Box. You think that is the only way it can be done because you have no experience or knowledge of electrical codes. I would also bet you have no idea what the earth ground is for. Fact is the code offers you all kind of options.
250.50 Basically states all electrodes available at a building or
structure defined in 250.52 (A1) through (A8) shall be bonded together and used. Where none exist electrodes using 250.52 (A4) through (A7) shall be used.
- A1. Metal Underground Water Pipe
- A2. Metal Frame of building or structure.
- A3. Concrete Encased Electrode
- A4. Ground Ring
- A5. Rod and Pipe aka 8-foot ground rods or 3/4-inch conduit used as raceway for the PV conductors.
- A6. Other listed electrodes
- A7. Plate
- A8. Metal underground objects.
What your inspector is going to look for to comply with 250.53 (2) is that you are using at least 2 Electrodes from the choice of the 8 above. So you have Concrete Encased Electrodes sort of, and Metal Framing embedded into the concrete sort of so an Inspector might or might not want a good know electrode like a Ground Ring.
All a Ground Ring is ring encircling the structure of not less than 20 feet, in direct contact with dirt, and a minimum conductor size of #2 AWG conductor. In other words dig a shallow trench around the structure say 6 inches deep, lay #2 AWG tinned bare solid copper, and bond it to one of the post encased into the concrete.
The two best electrodes are Concrete-Encased and Ground Rings. It will make the inspector smile and give you a check mark (done).
FWIW do not confuse ground with equipment ground. They are not the same and have different functions.