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I'm install a new 100 amp service to a detached garage. I'm installing a grounding rod and need to know the proper installion. I've heard tying to the meter, or to service panel through pvc conduit, and various other techiniques on forums. I just want the correct way to ground a new 100 amp service. I have no plumbing at the garage either. Thanks
 

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You should use a 4 wire feeder. H-H-N-G. The ground goes to the ground terminal strip in the panel and from there to one or two ground rods. You cannot run the ground (GEC) separate from the feeder. It all must be in one conduit or cable. You need a #8 green or bare and #3 for the hots and neutral, if they are copper. This ground/bonding wire needs to have the same potential as your service bonding grid.
If you are not under the 2008 code cycle 3 wire feeders are allowed. I would still use a 4 wire feeder regardless.

Ps..Connect the ground in the main panel the same way. To the grounding terminal strip.
 

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I'm using #2 copper for 2 hots and 1 neutrals. I used a 5/8 x 8' grounding rod and using a #6 bare ground. When connecting the ground in the panel do I need to separate the neutrals on one side and grounds on the other or do I just connect the #6 bare ground with my #2 copper neutral. Thanks
 

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I'm using #2 copper for 2 hots and 1 neutrals. I used a 5/8 x 8' grounding rod and using a #6 bare ground. When connecting the ground in the panel do I need to separate the neutrals on one side and grounds on the other or do I just connect the #6 bare ground with my #2 copper neutral. Thanks
DO NOT connect your neutral and ground wire under the same terminal. These need to be isolated from each other. Your "bare grounds" (EGC's) and neutrals from your branch circuits also need to be isolated. Oversizing your conductors as you have is a good thing, not a code violation.

Good luck.
 

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The OP says he ran just three wires, which if he is still under the 05 Code and has no other metal pathways, is compliant. In this case the neutral and ground are bonded, just like a service entrance.
 

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I'm using #2 copper for 2 hots and 1 neutrals.
You should have 2 hots, a neutral and a #8 ground. Even if you are not under 2008 code, it's the right way to do it.

The ground rod wire and equipment groind from the panel go to a ground bus along with all the groind wires in your garage circuits.

The neutral bus in the garage panel must be isolated from the enclosure and the grounds.
 

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OP. Have you already installed the feeder? :whistling2: If you only have three wires, Househelper provided your answer. If you have not installed/buried the feeder, please use 4 wires. H-H-N-G.

If you installed a 3 wire feeder you cannot bring any other metallic pathways from the main service structure to the unattached structure. Metal water lines, Telephone lines and any and all other metallic pathways will be prohibited. :eek:
 

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As others have stated the nec recently switched from 3 wire to 4 wires in this situation. Either way you should also drive 2 ground rods
 
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