Sub-panel or main panel?

Even if it was a 4-conductor feeder?

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Where is the main disconnect on these typically?

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Good point, these scenarios are usually on the same building… so never mind.
That’s why this convo got me thinking, and a little confused :smiley:

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I’m with ya brother. Just trying to keep up myself!

My question then becomes does the fact the main disconnect is not directly attached to the building in the OP’s situation make all the difference?

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Too bad we cant count these forums as continuing education for state requirements :smile:

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Yes, I believe so

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That would make a difference. A feeder within the same structure would always be required to have an EGC run as part of the feeder. A feeder to a separate structure installed prior to the adoption of the 2008 NEC would not, in that scenario a 3-wire feeder is permitted and the neutral is bonded at the separate structure. There would also need to be no parallel paths for the neutral current between the two structures. Here’s the 2005 NEC and the 2008, you can see the change. The 2008 and later code cycles apply only to existing structures.

2005 NEC:

250.32(B)(2) Grounded Conductor Where (1) an equipment grounding conductor is not run with the supply to the building or structure, (2) there are no continuous metallic paths bonded to the grounding system in each building or structure involved, and (3) ground-fault protection of equipment has not been installed on the supply side of the feeder(s), the grounded conductor run with the supply to the building or structure shall be connected to the building or structure disconnecting means and to the grounding electrode(s) and shall be used for grounding or bonding of equipment, structures, or frames required to be grounded or bonded.

2008 NEC:

250.32(B)Exception: For existing premises wiring systems only, the grounded conductor run with the supply to the building or structure shall be permitted to be connected to the building or structure disconnecting means and to the grounding electrode(s) and shall be used for grounding or bonding of equipment, structures, or frames required to be grounded or bonded where all the requirements of (1), (2), and (3) are met:
(1) An equipment grounding conductor is not run with the supply to the building or structure.
(2) There are no continuous metallic paths bonded to the grounding system in each building or structure involved.
(3) Ground-fault protection of equipment has not been installed on the supply side of the feeder(s).

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Daniel, I did not have access to the panel next to the meter.

Thanks to all that provided input. I was unable to gain access to that panel by the meters so I can’t say whether it is 3 wire or 4 wire. I would think the panel below the meter is the main disconnect. Seems like most of y’all agree the panel attached to the house is a sub panel that’s just wired a little differently? Am I correct in that assessment?

My thinking is that if this is a sub panel, the tie rod connecting the neutral and ground bus bar should be removed.

I suppose I can always recommend further evaluation by a licensed electrician.

It’s a 3-wire feeder because there are only three conductors in the feeder raceway at the panel. The tie cannot be removed because there is no EGC run with the feeder. It must be left just the way that it is because the bonded neutral is providing the equipment grounding. The only way it can be changed is if a 4th conductor, an EGC is pulled in the raceway. IMO given when it was installed and inspected there is nothing out of the ordinary therefore there is nothing to evaluate.

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