# New Meter pan combo and existing service panel/sub panels



## Jbrad (Aug 29, 2017)

I am installing a 200 amp meter pan / main combo. As I understand it, my existing 200 amp service panel becomes a sub panel and I must separate the netural and grounds (un-bond). That's the easy part. I also have an existing sub panel in a detached building that is fed with only a three wire service where a ground rod is bonded with the neutral as per code in 2001.
It seems that my only option is to run a 4th conductor as a grounding conductor. Is this true? If I leave my detached building sub panel as is, my existing service panel, now also a sub panel, will not be un-bonded because of the bond at the detached building sub panel. Any suggestions would be greatly appreciated.


----------



## sbrn33 (Mar 15, 2007)

Jbrad said:


> I am installing a 200 amp meter pan / main combo. As I understand it, my existing 200 amp service panel becomes a sub panel and I must separate the netural and grounds (un-bond). That's the easy part. I also have an existing sub panel in a detached building that is fed with only a three wire service where a ground rod is bonded with the neutral as per code in 2001.
> It seems that my only option is to run a 4th conductor as a grounding conductor. Is this true? If I leave my detached building sub panel as is, my existing service panel, now also a sub panel, will not be un-bonded because of the bond at the detached building sub panel. Any suggestions would be greatly appreciated.


Can you get that subpanel wire to your new meter main? I think you would be OK then.


----------



## Jbrad (Aug 29, 2017)

The detached building sub panel is 150 ft away and the feed is not in conduit which means I would need to trench it in. Wouldn't the grounding conductor need to be run with the three wire feed?


----------



## sbrn33 (Mar 15, 2007)

Jbrad said:


> The detached building sub panel is 150 ft away and the feed is not in conduit which means I would need to trench it in. Wouldn't the grounding conductor need to be run with the three wire feed?


Not if you can get it back to your new Main panel. Grandfathered. And safe as hell.


----------



## Jbrad (Aug 29, 2017)

Thanks sbrn33. Just so I understand, adding the grounding conductor is the only way to be code compliant. Correct?


----------



## sbrn33 (Mar 15, 2007)

Jbrad said:


> Thanks sbrn33. Just so I understand, adding the grounding conductor is the only way to be code compliant. Correct?


No, you are grandfathered in with the 3 wires if you can get it fed from the new main panel. You may want to check with your AHJ but that is how it would work here. 
Honestly if it was my own place I would have no problem leaving it the way it is.


----------



## Jbrad (Aug 29, 2017)

Thanks again for your help. I may be able to feed the detached building from the new service without to much work and I will get approval from AHJ.


----------



## MechanicalDVR (Dec 29, 2007)

Jbrad said:


> Thanks again for your help. I may be able to feed the detached building from the new service without to much work and *I will get approval from AHJ.*



:thumbsup:

Best place to start!


----------

