Does this metal raceway need a bonding jumper?

I’m doing an inspection and got my hands on a prelisting report. The previous inspector called this out for not having bonding provisions for the metal raceway. To me, it looks like it has pretty good connectivity to the metal panel enclosure which is grounded.

Does this raceway need bonding, you think?

Since there are service entrance conductors within that service raceway it needs to be bonded by something other than a standard locknut which is what is visible in the photo. If there are concentric or eccentric KO’s (there are concentric KO’s on the meter enclosure) then a bonding bushing is required. Only one side of the raceway requires the additional bonding so in this case a bonding bushing could be in the meter enclosure. If there are no concentric or eccentric KO’s then a bonding locknut is permitted in lieu of a bonding bushing. Looks like there are some other issues as well.

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What else do you see? I’m still here

The backfeed breaker could use a retaining mechanism.

shoot, why am I not familiar with either of those phrases?

does a retaining mechanism keep a large breaker from disconnecting itself from the panel when and if it trips?

When a breaker is back-fed, it is supplying power to the panel and is required to be secured to the panel. If it comes loose, the breaker is still energized.

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of course, thank you!

Here is one from today…it is secured.
image

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Robert, did you mean to say “if there are” ?

Yes that is what I meant thanks for pointing out the error. I’ll fix it.

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Thank You! for taking the time to inform us newer guys. Always a treat and something to learn from reading your posts.

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You’re welcome, I’m always happy to help when I can.

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Hi Robert, how could/would/should a home inspector identify if the required additional bonding is in the meter enclosure, thus not erroneously calling out missing bonding?

Good question. Most meter enclosures are locked so they cannot be accessed. For a home inspection I would simply report what is visible (in this case no additional bonding) and defer to an electrician.

There was an open knock out on the bottom and I’m fairly certain there wasn’t, so I felt comfortable giving it the “may or may not” treatment.

Plus the client gave me the previous report, so I didn’t want to give them the impression that it was dealt with I guess.

Certainly easy enough. I have been reporting on it the same way as I do gas pipe bonding that I cannot confirm.

How about the bare conductor we see coming from the raceway (assumabley the meter) to the buss? What would this indicate to us?

I agree it looks like it comes from the meter. Could be:

  1. a bonding jumper to the meter enclosure/neutral bus (or what someone thought was an EGC) or
  2. a bonding jumper to a bonding bushing on the raceway inside of the meter.

The 1) would not be permitted because it is in parallel with the neutral. This would create objectionable current and is a violation of 250.6(B). When the metallic meter enclosure is ahead of the service disconnect it is bonded directly to the neutral. The neutral in the panel is also bonded via the MBJ (green screw). Since both metal enclosures are bonded to the neutral there is no need to run a 4th conductor (the bare #8) between the two enclosures. (Think of a 3-wire SE cable typically run between the two which is code compliant).

Unless the bare conductor in question is providing the require bonding of the metal raceway via a bonding bushing inside of the meter enclosure it should be removed. Now having said all of that not removing it might never cause any issues.

Great to know! I knew there was something about parallel path but again the specifics were beyond me…until now.

I see that jumper configuration a lot in our area & have been inclined to think it is a bonding jumper to a bonding bushing on the raceway inside of the meter. Obviously, I cannot ever confirm its use since we don’t access meter box so I report the raceway & defer to an electrician.

report what exactly?

You can’t report what you can not see. Always assume everyone did their job correctly until you SEE differently. It’ll save you from a lot of complaints.

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