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Hi, we're installing a new electric service and I have a grounding question. The meter will be installed permanently on a 6x6 pedestal. The utility requires two grounding rods at the meter pedestal and another two grounding rods at the house. We're temporarily installing a load center on the pedestal, but later it will be removed when we add a 300 ft underground service to our build location. Based on the utility's requirements, I assume we need to bring the ground wire into the meter panel. I've seen some videos of people that ground the load center instead, but since our load center is temporary I would rather ground the meter as it will be in the final installation. I'm unsure of how to ground the meter. Would I just install a grounding bar in the meter? Secondly, would I need to run a ground from the meter to the load center, or is that not required since the neutrals are bonded to the enclosures? Below are my utility's grounding requirements. I want to avoid having to run a 4 wire cable 300 ft later on if possible.


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The instructions call for the grounding to be in the service, not the meter.
 

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The instructions call for the grounding to be in the service, not the meter.
Hi, thanks for your reply. I agree, the first sentence does say the service needs to be directly grounded. But it also says two grounding electrodes need to be installed near the house. So it could be referring to those two grounding electrodes, not the two electrodes installed at the meter pedestal. I live in a rural area and the utility requires the meter base be installed 15 ft from the pole, so I think a lot of people have an installation with two sets of grounding electrodes. Their drawing shows two grounding electrodes at the meter pedestal (see below).

A later sentence says that a 3 wire cable can be run from the meter pedestal to the house if there's no disconnect at the meter pedestal. So that's what makes me think they are specifying that the meter base should be grounded if it's on its own pedestal away from the house. In this case a 4th ground wire wouldn't need to be run to the house.

This is what I'm guessing, but I think I will just contact the utility on Monday for clarification.

On the plus side, I partially answered my own question, the meter base I purchased has a terminal to accept a ground wire.

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So far, all you've asked about is power company requirements. The power company can wave their opinion around all they want. They can even refuse to connect you if you don't follow their private rules. But they can't make their rules the only rules. They don't have the authority to override NEC.

NEC requires you to ground the service point, which is the first disconnect past the meter. At the service point, neutral is bonded to ground. All wire past this point must carry neutral and ground separately and keep them isolated.

However I believe on a pole/pedestal service like that, NEC requires there be a disconnect at the meter, which makes that the service point! The power company couldn't care less about that.

But this will kill 2 birds with one stone: it grounds the service point and the meter as well. Like I say, metal conduit between the 2 and you're done.
 

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NEC requires a disconnect outside the premise now - a meter/main could fulfill that requirement or not depending on your AHJ interpretation. But considering that the meter will be 300' from the structure, wouldn't you want a feed-through service out there anyway, for any electrical needs you may have 300' away from the house? (I'm picturing a rural driveway into the woods,with the service meter located right off the roadway.) Post light, yard light, electric gate...
 

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Hi all, thanks for your input! The meter base is in a location where we wouldn't necessarily need power. It's not at the base of the driveway (it's about 200 ft away). It's just on the edge of the road with a lot of forest behind it. Only thing we might want down there is a security camera, but not sure that would be worth the cost of running the extra conductor 300 ft. I would love to run metal conduit 300 ft but I think it would be far too expensive!
 

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Hi all, thanks for your input! The meter base is in a location where we wouldn't necessarily need power. It's not at the base of the driveway (it's about 200 ft away). It's just on the edge of the road with a lot of forest behind it. Only thing we might want down there is a security camera, but not sure that would be worth the cost of running the extra conductor 300 ft. I would love to run metal conduit 300 ft but I think it would be far too expensive!
ENT or PVC wouldn't be that expensive.
 

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Here's a novel idea. Perhaps rethink the situation and instead of mounting your panel on the meter post run the power to a temporary job-site power pole. That's a very standard way of operating a job site. Locate it such that the feeders will be long enough to reuse for the permanent building service disconnect later. A little planning could save you some dough. Later redigging the end portion of the run and swinging it in alignment and trimming to length could all be possible. Explain the plan to your inspector so he will not require you to dig up the entire run for a second inspection.

Keep in mind that the code ( 310.15(B)(7)(1) through (4)) allows you to calculate the feeder load and consequently the conductor size by a factor of 83% for dwelling services. Run aluminum wire feeders.
 
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