For example the national electric code requires no greater than 25 ohms of resistance in a ground system.
Ground rod resistance to earth.
For instance if a ground rod is driven into a very rocky and dry area it may not conduct electricity into the ground well.
Ground ring ground rods.
2 point dead earth method.
You should measure the resistance of an electrode with respect to the surrounding soil in the area.
Run the wire to your test location.
If you do not have one already you can easily install a ground rod for your home.
The goal in ground resistance is to achieve the lowest ground resistance value possible that makes sense economically and physically when contacting the earth also known as the soil ground rod interface.
To properly test the resistance of a ges you must follow some simple rules.
Four of the most common methods of ground resistance testing used by test technicians are discussed below.
Go back to ways to improve earth electrode resistance 3.
The lower it is the better job it does.
In some instances ground rods can be installed in areas where the earth has a lot of resistance.
The procedures for earth resistance testing are referenced in ieee standard no.
For a safe electrical system your ground rod resistance should have a very low resistance value.
The rule is that the lower the resistance it has the better job it does.
You can only do this by using the fall of potential method with a three terminal earth ground resistance tester.
Chemical treatment of soil is a good way to improve earth electrode resistance when you cannot drive deeper ground rods because of hard underlying rock for example.
Unfortunately as time goes by factors such as ground rod corrosion soil moisture high salt content high temperatures and loss of contact of your wires as well as others may increase the resistance of ground rod s hence affecting its effectiveness.
Make sure that you have stripped back the insulation from both ends of the wire to allow for a good connection.
The function of any ground rod is to dissipate the current that is recovered in any faulty electrical circuit near your house to the earth surrounding the ground rod.
Step 1 connect your length of wire to a metal stake in the ground.
Treatment of the soil.