ECN Forum Forums General Topics of the Trade General Discussion Area Proper Grounding

I just finished hooking up my new service to my home. As I was grounding the service disconnect panel, I got wandering. Is there a good way to check for a good ground at the ground rod.

In the past installations I have done, I use the reccomended ground rod for the soil type and area. (example - 5/8" x 10' for sand) If in doubt, I always go bigger. But is there a way to check to see if that is sufficient. Thanks, Kevin

There are numerous ways to check the ground rod resistance, this can be a fall of potential test which uses somewhat expensive testers, it can be a clamp type meter, you can actually apply voltage and use an amprobe. The truth is, the required 25 ohms at the ground rod doesn't mean much at our voltage levels, and unless you are shooting for some "performance" level of grounding, you are better off just driving two rods and then head to the house.

Roger

The traditional method used here for decades is the fall-of-potential method mentioned by Roger.

There's a description of it, along with other useful notes here. .