#### K8MHZ

##### Senior Member

When we say we have a grounding electrode resistance of say, 5 ohms, what does that mean, exactly? IOW, we have a resistance of 5 ohms from the electrode to what? 'The earth' is always the answer I get, but I really don't understand what that means. Resistance is a value measured from two points. How can 'the earth' be one of those points?

For example, if I have two individual electrodes that measure 5 ohms by accepted testing procedures and they are a hundred or so feet apart, would there be 10 ohms of resistance between the two rods? I would think not. But maybe I am wrong.

I have read the methods for ground rod testing (AVO has a good book on it) and know how to do it, I just don't really understand it perfectly.