The National Electric Code in the US can get very complicated. I do not know about code in Mexico – most we see does not appear to comply with codes we are aware of in the US.
In residential construction the standard used to be to pound an 8 foot length of 5/8” copper rod straight down into the ground. This is almost impossible to do by hand unless you are pounding into sand. A trick is to use a “chipping hammer” (see web address below – they usually cost from $300 to $800 – can be rented in the US). But if you were to put something like this in the ground in an RV park you would probably want to get it back (they are not cheap) and pulling one out can be more difficult that putting one in. With today’s electronics it is possible that some residences might require a more substantial ground than the old standard – I do not know for sure.
When you get into commercial electric it gets more complicated. As near as I can tell it is acceptable under certain circumstances to use METAL water pipes (preferably copper) that are known to travel underground for at least 20 feet. Some code stuff can be found at website I list below if someone wants to try to figure it out.
The reason for not pounding rebar into the ground which was brought up in this thread is the risk of hitting an electric line or a water pipe. Unless you know what is below where you are penetrating the earth it may not be a good idea to risk this. It may be possible to determine where the electric and water going to your hookup might be going in the ground – this would be on an case by case basis.
Some years ago I found a 5 foot length of stainless steel rod ½” diameter that was sold as a temporary ground rod. I cannot remember where I got it. I have not had to use it so far. So far in Mexico (and the US) I have been able to find another space/site within an RV park that has good ground if the first one I am assigned does not pass my tests. I do know how to use a multimeter to test all this stuff but not everyone does nor should they be expected to. We previously brought up some ways to do most of the tests and the tools needed. Below is a web address that might shed more light on all of this.
There are ways to test how good your ground is but as far as I know it requires special equipment and I do not know how to do it.
Today’s RVs are loaded with electronic devices – and most of us have computers in our RVs. We have had our inverter fried (I think it could have been a nearby lightning strike but never sure). As mentioned, today’s refrigerators and inverters and microwaves and clocks and far too many components to name all have some kind of electronics in them. Electronics are usually pretty delicate – they run on low power – so it does not take much to overpower and burn them up. I am trying to stay away from technical talk. Quite a few years ago we had lightning take out half our entertainment system. A TV antenna up high can be an attraction for lightning. One of mine got hit twice – outside my house.
If you are connected in any way to shore power and there isn’t a known good ground then you may be increasing your chances of a lightning strike. I am not sure how susceptible to lightning a free standing RV might be. A ground rod can provide some margin of safety.
We need to be aware of protecting ourselves and our equipment. Most of the places we have been in Mexico have had OK electricity (even grounded outlets) but we have been places where electricity is bad and not safe. By this I mean specific spaces in specific parks – this is not about the power company and the electricity they supply. But we test every outlet we plug into just to make sure. Much of this was explained in previous posts in this thread. We have found bad outlets and bad power in the US as well.
http://www.ecmag.com/section/safety/dirt-ground-rods
http://www.psihq.com/iread/strpgrnd.htm
http://rvsafety.com/wp-content/uploads/2013/07/AC_Electrical_Safety-GS.pdf
http://www.dewalt.com/tools/hammerdrills--hammers-compact-sds-rotary-hammers-d25330k.aspx
