Testing for proper grounding

[jason12000]

What is the best way to test for a "good" ground on a residential breaker box. What are the signs that the minerals in the soil around the grounding rod are used up, or the rod it's self is deteriorating.

[Core_d]

Fluke has test instruments designed for such a thing. They are not cheap.

[jason12000]

Nothing that can be checked with a conventional meter? Thanks for responding so quickly.By the way I'm from Wilmington, OH. Go Bucks.

[lytning]

Mike holt did a thing on checking ground rod resistance. Put 120 volts to the ground rod and used an amp clamp.

[jason12000]

Do you have a link to that test? Thanks for the response.

[Core_d]

Mike holt did a thing on checking ground rod resistance. Put 120 volts to the ground rod and used an amp clamp.

Yea, hows that work?

[timebuilder]

What is the best way to test for a "good" ground on a residential breaker box. What are the signs that the minerals in the soil around the grounding rod are used up, or the rod it's self is deteriorating.

As said, the device is not cheap, and it tests two distances from the ground rod. It is specially designed for the task.

AEMC-Understanding-Soil-resistivity-testing.png

[WyrTwister]

If in doubt , you can drive a second ground rod ( at least 8' x 5/8" ) , at least 15 foot from the existing one & re-do the ground wire , w/o splices , to both . Run at least # 6 copper , in one continuous length from the service panel , to the 1st rod & then to the 2nd rod . I recommend 1 piece direct burial clamps , such as JAB58 .

Or , in in further doubt , use 2 new copper clad / plated ground rods ? There are other ways to " make " ground electrodes .

God bless
Wyr

[moctod]

Easiest method to test ground resistance on a residential ground rod is with a clamp on ground resistance meter. Several companies have them including Fluke, Amprobe, AEMC etc. Most reputable electrical contractors should have one. Be sure that ground bar is bonded to neutral in service entrance panel to get correct reading.
Testing the soil resistivity (mineral content, etc) is a whole different ball game and must be performed using the fall-of-potential testing method. Meters used for this test can be used to test ground resistance also. Grounding probes are driven at set distances from the ground rod depending on the depth of the grounding electrode. Resistance is measured at each interval. To use this method the neutral-to-ground bonding strap in the SE panel should be removed. Specific requirements and techniques are too involved for this discussion but this gives you the general idea.