Quote Originally Posted by Randyj View Post
Jim,
in the area where I live the dirt is so full of minerals that it is no problem to get a current to travel through the ground. As far as voltage, I get as much voltage through my ground rod as I do through my neutral.... and it's 200 ft to the transformer. A magnet will pick up all kinds of small rocks in my yard. Of course, we're not all that far from Birmingham which is known for it's iron ore and this is coal country too.
Basic Electricity 101 we learn that the voltage drop across one resistor in series will be equal to the applied voltage.
From your service back to the transformer through earth would be one resistor in series no matter how many rocks you magnetic will pick up.

It is not a matter of how much voltage is present it is a matter of how much current will travel through this resistor (earth).

Check the resistance of your rod using the three point resistance test for ground rods but the equipment is very expensive. You could use a clamp-on resistance tester but they aren’t very accurate.
This will tell you the amount of current that will travel throung earth at your house.