Grounding when new panel is installed beside the old one

[rlcguy]

This may be in another thread, if so please point me to it. I saw a panel the other day where the homeowner(HO) had put a new panel in a couple of feet over from the old one. The guts were gone from the old panel and all circuits were just wire nutted to wire from the new panel. All of the grounds had been left in the old panel on it's grounding bar and a #12 had been run from the old panel to the new ones grounding bar. My question is this - shouldn't the ground from new panel to the old one be sized for the largest circuit in the conduit which was 50 amps for the range? Any thoughts or other threads to read would ba appreciated.

Thanks.

 

[jumper]

I think this install violates 300.3(B).

 

[petersonra]

I think it is a perfectly safe installation (other than possibly the undersized ground for the 50A circuit) that may well violate the code in a legalistic way. Ironically, it might well be in compliance on all counts if a nipple was used to connect the two panels and no ground wire was run at all.

 

[petersonra]

I think this install violates 300.3(B).

how do you figure that? as long as an appropriate sized egc is run in the same raceway as the extended conductors, how is this a violation?

it might be a violation of how many CCC can be put into a piece of conduit that runs between the old box and the new one.

 

[Dennis Alwon]

It is a violation because the egc needs to be sized to the 50 amp circuit- #10. Correct that and it's a good install. I am assuming the neutrals are all moved to the new panel with the circuit conductors,

 

[rlcguy]

Thanks to all who have commented:thumbsup:. I believe Dennis is most correct, and would point out that all of the neutrals were extended to the new panel. Jumper, could you please elaborate on why you think it may be a violation in case I am reading 300.3(B) wrong?

 

[petersonra]

It is a violation because the egc needs to be sized to the 50 amp circuit- #10. Correct that and it's a good install. I am assuming the neutrals are all moved to the new panel with the circuit conductors,

Would it be compliant if it was EMT run between the old and new PBs? Or would the smallish ground wire still be an issue?

Its more than 2 feet so wouldn't compliance require larger conductors to meet the derating requirements for more than 8 CCC if they were all run in the same pipe?

 

[jumper]

Jumper, could you please elaborate on why you think it may be a violation in case I am reading 300.3(B) wrong?

Simple, I was wrong. The set-up threw me off and I was confused. Not an uncommon occurrence.