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I'm replacing a meter socket (upgrading to 200A) operating under NEC2017, and saw something I didn't see on the old socket.

Current setup - a 200A capable main panel, with 4ga stranded wire coming out of the panel to an 8ft ground rod, which is connected to another 8ft ground rod with a 4ga solid copper wire 8ft away, as well as a 4ga (green) wire going from the panel to the water pipe. MainPanel

The picture below is of the new meter socket (Milbank U4801-Xl-5T9). I am not sure how to interpret the red label saying "When service not grounded, remove bonding strap and re-install screw" Meter Socket

Red Label

I am not sure if this in reference to the service from the pole, or my service panel. I have seen folks throw a grounding wire into the meter socket directly (pic below from a This Old House video on upgrading to 200A service), but my ground is on the main panel. My current inclination is to leave the bonding strap in place (but remove the label as it seems to be partially insulating the screw from the strap), as my service panel is grounded. Is this the right approach?

Many thanks in advance.

This old house

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    The location of the label doesn't affect the strap's grounding. The strap grounds via surface metal contact on the other side... not via the screw head. May 20 at 18:12
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    So many do not have a clue that the NEC starts after the utility rules check the utility requirements are they supersede the NEC, don’t believe me put in a totally code legal meter base that the utility will not approve and you will not have power to worry about. Most meter based and mains are required to be bonded by the utility. But what do I know I am not an internet only electrician. I see no questions on the jurisdiction,,, that would be my #1
    – Ed Beal
    May 20 at 23:20
  • Thank you Harper and Ed!
    – sil80
    May 21 at 15:39

2 Answers 2

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Leave it there

Since meter sockets sit upstream of the service disconnecting means, and thus the system neutral-ground bond, they're required to be bonded to the neutral. So, don't mess with that jumper -- futzing with it is only needed in some weird applications (such as revenue production metering in some solar systems).

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  • Much appreciated, ThreePhaseEel!
    – sil80
    May 21 at 15:38
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Experts may have a more specific answer for your particular situation, as it can get extremely technical, plus NEC version can make a difference, as well as local and/or utility rules. (Listing your city/state and electric utility may be relevant here.)

But the basic concept is (has not always been this way): Neutral grounded to bond in exactly one location. This meter box comes with the bond in place - i.e., neutral bonded to ground. If the service is "not grounded" that means "it is grounded someplace else, so don't ground it here" --> "remove the bond (the metal strap under the red label, currently held down by the screw). If the service is supposed to be grounded, leave it as is (the red label is not blocking the neutral ground bond).

But if the service is to be grounded then you would remove the neutral ground bond from your main panel (so that it is only bonded in one place) and you would need to separate grounds (to only be on ground bars) from neutrals, and there may be an issue (I truly don't know) of where the ground wire to the ground rods terminates. Speaking of which...

  • The ground wire to the ground rods should be solid, not stranded. This may be a local thing. Based on NEC 250.62 it can be solid or stranded.
  • The ground wire should be continuous - i.e., one wire that goes from the panel to one ground rod with a proper clamp and then to the second ground rod - no breaks/splices along the way, except with certain special types of splices (not your usual wire nuts).

And most definitely:

My current inclination is to leave the bonding strap in place (but remove the label as it seems to be partially insulating the screw from the strap)

Do NOT do that. The screw is providing pressure the metal bonding strap to hold its nice big surface area against the surface area of the box, plus the screw threads are connecting both. Whether the washer actually contacts the surface of the bonding strap is irrelevant. But removing an important label is never a good idea - airplane accidents and other serious things have happened because labels were removed.

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    AIUI, Nothing requires solid grounding wire, and grounding wire can be "irrevocably spliced" or cad-welded. Protection from damage where exposed to damage may vary with the type/size of grounding wire.
    – Ecnerwal
    May 20 at 16:27
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    Yep. 500 MCM for pole-to-meter power. 350 for pole-to-meter neutral. Coulda been 1/0 for ground, I guess, looking at charts. Runs out to my 100 foot well casing, has 5 driven rods along the way for amusement value.
    – Ecnerwal
    May 20 at 17:09
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    Here is one link referring to the interrupt-ability of the grounding conductor: diy.stackexchange.com/a/249010/121651
    – sil80
    May 20 at 17:11
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    Cannot give an up vote the conductor can be solid , stranded insulated or bare, smaller sizes require protection but a code reference is the only one that is code compliant, please don’t even link my comments or answers unless a specific reference is provided.
    – Ed Beal
    May 20 at 23:29
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    Took me a couple of minutes to find the wording in an old code book 250.62 , NEC 2014 , but there is another section that prohibits the conductor from being aluminum if within 18” of earth… but what do I know I can’t make this 3 pages long but there is the code ref. Oh and this has been code since the 70’s
    – Ed Beal
    May 20 at 23:40

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