Abandoning nipple

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Flatpad

Member
Location
NJ
I have a new situation to me. Currently there is a meter can on the outside of the garage wal and a main breaker panel on the inside, they are connected with a metal nipple. A #4 wire runs from a lug on the neutral bar in the mater can to a bonding bushing in the meter can, through the nipple to a bonding bushing on the panel side, then up to the ground bar.

I am going to be abandoning that nipple because I will be coming out of the side of the meter can to an ATS, and then run from the ATS into the garage and into the panel.

The question is this: What is the best way to abandone this nipple? Leave it exactly the way it is? Removing the bonding conductor from the lugs and bushings and just leave the pipe? Pull everything off and remove the pipe, then insert KO seals from inside of the meter can and panel (is that compliant)?
 

Flatpad

Member
Location
NJ
Now that I think about it, that ground wire that I explained above* is probably violating the parallel conductor rules since it's smaller than the neutral seervice conductor. Odd since this is a relatively new installation that passed inspection a few years ago.


*" A #4 wire runs from a lug on the neutral bar in the mater can to a bonding bushing in the meter can, through the nipple to a bonding bushing on the panel side, then up to the ground bar."
 

Smart $

Esteemed Member
Location
Ohio
...

Out of curiosity, would it matter that the panel that the bonding conductor is connected to is no longer the main disconnect?
Yes, you have the EGC connected to the grounded conductor after the main bonding jumper. However you decide to do it, the panel EGC needs to be electrically isolated from the grounded conductor.
 

kwired

Electron manager
Location
NE Nebraska
Leave it if you want, just make sure that it hits EGC bar and not neutral bar in the panel when done. It should not be necessary, to have this wire but isn't a code violation either as long as it doesn't land on the neutral bar in the panel.

A single conductor in a metal raceway needs to be bonded to each end of the raceway - this is already done as is.
 

Flatpad

Member
Location
NJ
I'll have to move the wair over to a newly installed ground bar inside of the main panel when I move all the other EGC's, since that will no longer be the main disconnect anymore. But currently the wire bonding both ends of the nipple is also landed to the neutral bar inside of the meter pan. That's why I was debating removing the wire and nipple altogether as long as I had a compliant way to close the KO from the inside of the panel and meter pan.
 

Smart $

Esteemed Member
Location
Ohio
Apparently other posters aren't seeing it. Service neutral bonded to SUBpanel EGC. Violation.
 
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kwired

Electron manager
Location
NE Nebraska
Apparently other posters aren't seeing it. Service neutral bonded to SUBpanel EGC. Violation.

Only a violation if it lands on the neutral bar in the subpanel. You can easily have other conductive paths between the meter and the sub panel, but you need to prevent having objectionable current on these paths. Isolating the neutral in the sub panel (99% of the time that means removing the bonding screw) from other conductive elements accomplishes this. You are allowed to place bonding jumpers on anything you wish, as long as it doesn't create objectionable current from the grounded conductor flowing on components not intended to be current carrying.
 

Smart $

Esteemed Member
Location
Ohio
Only a violation if it lands on the neutral bar in the subpanel. You can easily have other conductive paths between the meter and the sub panel, but you need to prevent having objectionable current on these paths. Isolating the neutral in the sub panel (99% of the time that means removing the bonding screw) from other conductive elements accomplishes this. You are allowed to place bonding jumpers on anything you wish, as long as it doesn't create objectionable current from the grounded conductor flowing on components not intended to be current carrying.
Please review 250.142.
 

kwired

Electron manager
Location
NE Nebraska
Please review 250.142.

Is the conductor in question a "current carrying conductor"? It is not intended to carry current but may because of arrangement.

It likely will have some current on it because it does create a parallel path between the neutral terminal in the meter socket and the EGC of the subpanel via the bonding screw in the service disconnect.

You will have similar parallel via the nipple the OP wishes to abandon, or through any metallic structure between the same two points if one were to exist.

Good design will make attempts to minimize or eliminate objectionable current, but sometimes code compliant installs still have current flowing things not intended to be current carrying. Metallic service raceways is one such place where this can easily happen.
 

Smart $

Esteemed Member
Location
Ohio
Is the conductor in question a "current carrying conductor"? It is not intended to carry current but may because of arrangement.

It likely will have some current on it because it does create a parallel path between the neutral terminal in the meter socket and the EGC of the subpanel via the bonding screw in the service disconnect.

You will have similar parallel via the nipple the OP wishes to abandon, or through any metallic structure between the same two points if one were to exist.

Good design will make attempts to minimize or eliminate objectionable current, but sometimes code compliant installs still have current flowing things not intended to be current carrying. Metallic service raceways is one such place where this can easily happen.
The nipple will no longer be a service raceway. The nipple along with its bonding conductor should be removed for very reasons you cite, coupled with the fact abandoning in place would be non-compliant.
 

Flatpad

Member
Location
NJ
The nipple will no longer be a service raceway. The nipple along with its bonding conductor should be removed for very reasons you cite, coupled with the fact abandoning in place would be non-compliant.
Pulling it out seems like the best option. I just don't want any issues with the KO seals being installed from the inside of the panel and meter pan.
 

kwired

Electron manager
Location
NE Nebraska
The nipple will no longer be a service raceway. The nipple along with its bonding conductor should be removed for very reasons you cite, coupled with the fact abandoning in place would be non-compliant.

If they were both mounted on a steel structure you still have similar issues, the steel structure would see some current.
 

kwired

Electron manager
Location
NE Nebraska
Pulling it out seems like the best option. I just don't want any issues with the KO seals being installed from the inside of the panel and meter pan.
Why is that an issue? All that matters is that the hole be plugged, does not even have to be a "KO seal", just something substantially equivalent to the enclosure.
 
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