# Ground rods at a remote building



## heel600 (Oct 31, 2007)

Do I need the 2 ground rods at a barn sub-panel.

The service is in a different building. The barn has no footing, and no water.

I'm pretty sure the sub-panel in a remote building need a ground electrode, but I couldn't find the code reference.

Any help would be appreciated.


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## Speedy Petey (Jan 10, 2007)

See 250.32 . This will tell you everything you need to know.


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## heel600 (Oct 31, 2007)

Speedy Petey said:


> See 250.32 . This will tell you everything you need to know.


I know that button is around here somewhere... Oh here it is...

That was easy.

I just realized (now that I closely read 250.32) that circuits (not just feeders) need an electrode.

I guess that means if a run a light and recptacle to a small shed, then it needs an electrode. (Am I interpreting this correctly?) Never saw that done before.


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## Speedy Petey (Jan 10, 2007)

Actually no. 
If you see 225.30 says no more than one circuit or feeder can be run to a remote structure, and 250.32 tells us that a grounding electrode is required, BUT if only one circuit is run no electrode is required.

_*225.30 Number of Supplies
*Where more than one building or other structure is on the same property and under single management, each additional building or other structure that is served by a branch circuit or feeder on the load side of the service disconnecting means shall be supplied by only one feeder or branch circuit unless permitted in 225.30(A) through (E). For the purpose of this section, a multiwire branch circuit shall be considered a single circuit.
_{My note: (A) thru (E) have no relevance in a residence}
_*
250.32 (A) Grounding Electrode* Building(s) or structure(s) supplied by feeder(s) or branch circuit(s) shall have a grounding electrode or grounding electrode system installed in accordance with 250.50. The grounding electrode conductor(s) shall be connected in accordance with 250.32(B) or (C). Where there is no existing grounding electrode, the grounding electrode(s) required in 250.50 shall be installed.

Exception: A grounding electrode shall not be required where only a single branch circuit supplies the building or structure and the branch circuit includes an equipment grounding conductor for grounding the conductive non–current-carrying parts of equipment. For the purpose of this section, a multiwire branch circuit shall be considered as a single branch circuit.
_


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## gilbequick (Oct 6, 2007)

Also, if you run 3 conductors (hot hot neutral) to your subpanel you need to keep your grounds together in your subpanel. If you run 4 conductors (hot hot neutral ground) you need to keep your grounds and neutrals seperated in the sub panel. 

I don't have a code reference for this but I just got popped for it myself last week.


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## Speedy Petey (Jan 10, 2007)

Keep in mind Gil, this allowance was dropped for 2008, at least for those under the 2008 NEC. 

NO more new "3-wire" remote feeders.


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## JohnJ0906 (Jan 22, 2007)

gilbequick said:


> Also, if you run 3 conductors (hot hot neutral) to your subpanel you need to keep your grounds together in your subpanel. If you run 4 conductors (hot hot neutral ground) you need to keep your grounds and neutrals seperated in the sub panel.
> 
> I don't have a code reference for this but I just got popped for it myself last week.


Just a reminder - it is legal to run "3 wire" feeders (hot, hot, neutral) under the '05 and prior NECs *ONLY* when there are no other metallic paths back to the building it is fed from. No water, gas, intercom, coax, telephone, etc.

It would cause a parallel path for the neutral.


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## gilbequick (Oct 6, 2007)

Yes thanks, sorry forgot to add that little bit of info!


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