Ideally a ground should be zero ohms of resistance but.
Ground rod resistance check.
You should measure the resistance of an electrode with respect to the surrounding soil in the area.
The nfpa and ieee recommend a ground resistance value of 5 ohms or less while the nec has stated to make sure that system impedance to ground is less than 5 ohms specified in nec 50 56.
However we can estimate the resistance to ground using scenario b.
The lower it is the better job it does.
If this is the case for your ground rod the best solution is to drive a different rod into a different location.
For instance if a ground rod is driven into a very rocky and dry area it may not conduct electricity into the ground well.
Make sure that you have stripped back the insulation from both ends of the wire to allow for a good connection.
So if you are using 10 foot ground rods you must place.
To properly test the resistance of a ges you must follow some simple rules.
If your ground rods are placed at least one rod length apart you can use a formula to estimate the earth resistance of multiple grounding rods.
In some instances ground rods can be installed in areas where the earth has a lot of resistance.
Unfortunately there is not one standard ground resistance threshold recognized by all certifying agencies.
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.
An ideal ground rod resistance should be below 3 ohms.
R loop 10 ω 0 17 ω 10 17 ω.
The measurement of the loop resistance is relatively close to the resistance of the ground electrode being tested.
Multiple ground rods yield a lower resistance to ground than a single rod.
Step 5 measure the ground or leakage current if you wish to find out about the ground or leakage current all that you have to do is to set the rotary switch to ma or a.
Step 1 connect your length of wire to a metal stake in the ground.
Run the wire to your test location.
In areas where driving ground rods may be impractical the two point method can be used.
Ground ring ground rods.
For a safe electrical system your ground rod resistance should have a very low resistance value.
Check your clamp on tester s manual if it uses another kind of configuration.
P2 and c2 connect to a separate all metallic grounding point like a water pipe or building steel.
You can only do this by using the fall of potential method with a three terminal earth ground resistance tester.
