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My meter panel connects to an exterior service panel on the back of my house via a short stretch of NM conduit. The service panel has my main breaker and ties neutral to a grounding wire bonded to a buried rod.

Previously, my FiOS ONT was mounted next to the service panel. The telco installer bonded the ONT ground to the service panel ground by attaching a clamp to a corner of the metal service panel enclosure.

I have relocated the ONT and now it sits next to the meter panel. The grounding wire is not long enough to reach the service panel so I have mounted it to the meter panel. I figure the meter panel must be bonded to the neutral wire which is bonded to the grounding wire so we end up at the same place.

Any problem with this setup?

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  • Who's your electric utility? May 21 at 4:30
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    Dominion Energy (Virginia)
    – Stanwood
    May 21 at 4:32
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    What is NM conduit? Non-metallic conduit? Not a code recognized type. I'm having a difficult time understanding what a "meter panel" is and how if you mean "meter cabinet" how it is grounded if connected by some nonmetallic piping to the service panel. May 21 at 5:20
  • Verizon installed my FIOS ONT with ground wire clipped to the meter box. Dominion is my utility as well. May 21 at 13:05
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    Here's the thing. Meters are not inherently grounded. Generally they pick up ground via use of metal conduit connecting them to the service panel. However you say yours is non metallic. Unfortunate. May 21 at 17:13
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This is OK, as long as Dominion's happy, which they seem to be

Meter sockets upstream of the service disconnect generally pick up ground by being bonded to the neutral. (This is OK because you haven't hit the service disconnect yet, so there is no separation between neutral and ground at this point.) As a result, NEC 250.94(A) point 4 permits the Intersystem Bonding Termination (IBT) to be connected to the meter enclosure or to a bonding jumper connected to the meter enclosure.

However, since this is the meter enclosure we're dealing with, the NEC doesn't have the last word here. Utilities can and do set rules about the treatment of their cash register that go above and beyond what the NEC has to say about the topic, and some utilities indeed prohibit attaching grounding conductors or devices to meter sockets. In the case of Dominion, Section 240.11 of their Blue Book requires that bonding connections to the meter be made using an appropriate watertight (compression) fitting ("Kenny" clamp or equivalent) in a ½" KO to bring the bond wire into the meter base, where it can land on a dedicated terminal screw there.

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  • Thanks! This makes sense.
    – Stanwood
    May 22 at 2:07

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