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Suppose I have a setup like this: I take my power at a pole. The utility wants me to fit circuit protection there for a very long run to my house.

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By my read of things, this makes it a main panel and therefore this is the primary grounding point. And therefore the panel in the house is a subpanel.

Trying to answer this question, I found a NEC section (Article 310.15(B)(7) not to be confused with the table of the same number) which allows feeder in this case to be sized like service lateral, logical since it's doing the same job.

I would really, really like to have the neutral-ground bond at the house instead of the pole.

In my travels through NEC I could swear I saw a section that liberalizes where the N-G bond is in this case... and I thought might even permit omission of that long ground wire. But I can't find it again.

Can anyone help me find it?

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  • Install an isolation transformer then it would be a separately derived system and you could have the bond in the main panel. I don't remember being able to have the bond on a sub since the 99 code? Still looking. If there is a transformer at the pole 250.30.1 exception 2 might be close but I think it would still be a sub. In your case.
    – Ed Beal
    Commented Feb 28, 2018 at 19:22
  • When you say "The utility wants me to fit circuit protection there for a very long run to my house." The utility will usually run the underground to your house for a price and it would then be considered the service lateral since the meter would then be mounted on the house. Around here, our utility charges $4 a foot last time I used them. A little over $1000 for your situation. The service disconnect is the main point of bonding. NEC 205.24(A)(5) prohibits connection after the service with limited exceptions. I don't think your situation is one of the exceptions.
    – ArchonOSX
    Commented Feb 28, 2018 at 19:47
  • @ArchonOSX the application location has a utility that is a little weird. To be plain, I'm lifting this question from that linked question, because it's vexing me. He was unable to get the utility to serve at the house.
    – Harper - Reinstate Monica
    Commented Feb 28, 2018 at 21:21
  • @Harper -- out in the sticks, its actually rather common for the utility service to terminate at a pole on your property, with you responsible for bringing it the rest of the way to where it needs to go
    – ThreePhaseEel
    Commented Feb 28, 2018 at 23:21

2 Answers 2

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Yes, but only if you have a single, non-fused switching means at the pole, not a panel

You can do this if and only if the switch at the pole is a single switching means (fault-rated, non-fused disconnect switch), not any sort of panelboard, enclosed breaker, or fused switch. In this case, the switch at the pole becomes a hot-sequence meter disconnect (as opposed to the service disconnecting means), and is permitted by NEC 230.82(3):

(3) Meter disconnect switches nominally rated not in excess of 1000V that have a short-circuit current rating equal to or greater than the available short-circuit current, provided that all metal housings and service enclosures are grounded in accordance with Part VII and bonded in accordance with Part V of Article 250. A meter disconnect switch shall be capable of interrupting the load served. A meter disconnect shall be legibly field marked on its exterior in a manner suitable for the environment as follows:

                              METER DISCONNECT
                            NOT SERVICE EQUIPMENT

This may require consultation with the AHJ and/or utility -- they may require such a disconnect to be installed cold sequence i.e. ahead of the meter instead. This is normally only seen on socket-metered 480V services where yanking the meter out of its socket under load is a good way to get yourself roasted by arc flash, but nothing in the NEC prohibits a meter disconnect on a 120/240V service.

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This is along the lines of what ThreePhaseEel just posted. Note that I'm heavily paraphrasing from Ch. 17 Farm Wiring in Hartwell, Frederic P./ Richter, Herbert P./ Schwan, W. C. Wiring Simplified: Based on the 2017 National Electrical Code. Independent Pub Group, 2017.

In farm wiring it is common to install a meter on a pole (NEC "distribution point"). The neutral is grounded at the pole. The disconnecting means on the pole is termed a "site isolating device" to distinguish it from a service disconnect and the wiring leaving this device is service entrance wire conforming to the usual specifications.

We establish a service entrance at each building served directly from the distribution point. In the case of a (farm)house three-wire service would be the norm and the neutral is regrounded at the home as in a direct termination.

In higher amperage installations a current transformer is used to avoid running large wires down to the meter socket. The site-isolating switch can be double-throw to switch between the utility line and a generator.

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