Originally Posted By: dcarroll This post was automatically imported from our archived forum.
Inspected a house today where the service drop was on a detached garage. Below the meter was an exterior panel. There were no visible grounds here. The service then went under ground to the house. The only visible ground in the house was to the cold water pipe.
Originally Posted By: gbeaumont This post was automatically imported from our archived forum.
hi to all,
that is one odd set up, without seeing inside the garage panel, I have no idea whether it is grounded or not, just because it does not have a driven ground rod does not mean that there is no ground. It sure as heck should have one. (it maybe connected to rebar in the footing, or is it steel framed ??)
The panel in the house you say has a GEC on the water supply lines, that is normally OK, how old is the house/electrics ??
Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
Not enough info in the picture to say to much I will make some general comments.
The meter may or may not be to high, that is not covered by the NEC that would be a local utility requirement and each one is different.
The feeder from the garage to the house can be a four wire H, H, N, G or a three wire H, H, N.
Both buildings need some type of grounding electrode.
You say the house was using the water pipe as a grounding electrode which is good but it must be supplemented with one of the other types of grounding electrodes.
Originally Posted By: dcarroll This post was automatically imported from our archived forum.
This is a one year old home, and the garage is wood framed. I didn’t take this panel off because I didn’t like the fact that I was standing in a lot of vegitation, and I didn’t know if it was grounded or not.[/quote]
Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
dcarroll wrote:
Does the fact that the feed is H,H,N,G eliminate the need for a grounding rod for the inside panel? That is of course if the garage panel is grounded.
Nope all separate structures with feeders or services need grounding electrodes.
Here is just my guess.
The garage will have a concrete encased electrode and the wire for it is hidden in the wall, if you where to open the panel you would see it.
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The house also has a concrete encased electrode and because it has a water service it uses that too.
The concrete encased electrode would satisfy the supplemental electrode for the water pipe.
But this is just a guess, if you do not feel comfortable opening the panels that is fine but I do not see how you could make comments about the grounding or lack there of with out opening the panel.
Would a one year old house in this area have been inspected at the time of construction by an electrical inspector?
Originally Posted By: dcarroll This post was automatically imported from our archived forum.
You are absolutly right. Just couldn’t bring myself to open the outside panel. I need some education on concrete encased electrodes. I’m not sure what to look for.