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I have a meter socket box on a pole with a couple of circuits going to outside. I want to run some feeder wires to a service equipment box on a workshop structure thru underground conduit. Since the meter main is also considered a Subpanel and there is a ground electrode there, I am unsure of where the out the ground electrode and where to bond. Located in Central Florida

Daniel
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The meter main is not considered a subpanel. It is considered the main panel, hence the name. The basic setup is:

  • Hot/Hot/Neutral into meter main from utility. (Hots go to the meter, neutral bypasses the meter as the neutral current does not need to metered - it is always the difference between the hots.)
  • Neutral is bonded to ground in the meter main. This is the only place neutral should be connected to ground.
  • A ground wire going to an Ufer ground or 1 or 2 ground rods is connected to the meter main. This protects the building that the meter main is attached to.
  • One or more breakers are used to feed power to large loads and/or subpanels. Configurations vary a lot, depending on the number of breaker spaces in the meter main (a quick search shows anywhere from 2 to 42).

All circuits (whether a subpanel feed or an individual device) fed from the meter main will have at least one hot, a second hot or neutral or both (for a subpanel you would definitely have both) and a ground wire.

Any subpanel in another building needs to have its own ground rod(s) (1 or 2 or Ufer) connected to the panel. Neutral and ground are not bonded in the subpanel. Most subpanels come without neutral and ground bonded, but sometimes you will use a "main" panel as a subpanel out of convenience and/or cost, and then the neutral ground bond needs to be removed (usually just one screw).

manassehkatz-Moving 2 Codidact
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Speaking in terms of the equipment that is on the barn, that is formerly a meter-main and you now want to feed it from the meter on the pole... look at the labeling on it.

Suitable only for use as service equipment

That labeling will be your downfall.

North American standards require that at the first disconnect switch past the meter (which is almost always a circuit breaker), the neutral from utility supply must be bonded to the ground from the ground rods. Thus you have 4 things coming together: utility neutral, ground rod, house neutrals and house grounds. As such, house neutrals and grounds are allowed on the same bar, which does not need to be insulated from the panel enclosure.

Subpanels need isolation between neutral and ground.

Most panels/load centers capable of taking a main breaker, are configurable either way. The neutral bar is insulated, there's a bonding strap or screw that can be removed, and they sell accessory ground bars for like $6. Easy peasy. This equipment is labeled "Suitable for use as service equipment" since it can swing that way. (unlike, say, a 6-space panel with no possible location for a main breaker).

However, meter-mains are not like that. Because the meter is present, they assume the equipment will be Service Equipment and they don't necessarily provide a means to insulate neutral from ground. Because they don't provide that, they label it "Suitable ONLY for use as service equipment".

NEC 110.3(B) requires we follow the panel instructions and labeling, so that is that.

Now if you wanted to cheat it, and you had only a limited number of circuits to deal with, you could simply not use the neutral bar for neutrals, have the neutral wires bypass the normal attachment points, and use some alternate neutral-splicing method which physically and electrically floats - such as a Polaris connector or ILSCO Mac Block Connector. Then the former neutral bar becomes simply a ground bar, and there is no neutral bar - you are simply splicing it.

Harper - Reinstate Monica
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