Separate building and GEC

ArcLazerbeam

Member
Location
VT
Hey guys, question of the day. I'm doing a detached garage that will have two feeders going into it (House panel, and living space above garage.) This is all fed from the same service which is a 4 gang meter pack on the duplex, each feeder has its own 2" pvc. There's going to be a UFER once they pour the footer. However the state inspector is telling me I have to hit both panels with the GEC unbroken to UFER, I've never done a set up like this. Where is he getting this from?
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
You can run the GEC and tap off with a bonding jumper to each panel. The tap connections to the GEC do not have to be unbroken or irreversible.
 

ArcLazerbeam

Member
Location
VT
You can run the GEC and tap off with a bonding jumper to each panel. The tap connections to the GEC do not have to be unbroken or irreversible.
I figured as much.

I can't seem to find in the 14' where I am required to hit both panels. The closest I am getting in 250.32(A) which states

Building(s) or structure(s) supplied by feeder(s) or branch circuit(s) shall have a grounding electrode or grounding electrode system installed in accordance with Part III of Article 250...

it then bumps you down to 250.32(B) and (C) or 250.50.

I'm a grounding/bonding newbie it seems.
 

Smart $

Esteemed Member
Location
Ohio
I figured as much.
...
I'm a grounding/bonding newbie it seems.
It looks like you'll have to get a better grip of Code speak (terminology) first, then elaborate on what you have. In your opening post you said you have a 4-gang meter pack. Is that with or without mains. By mains, I mean service disconnecting switches and overcurrent protection, which can be in the form of fused switches or breakers. If this is the case then your use of the term feeders to garage is correct. Otherwise, they are service conductors.

Typically, you are only permitted one feeder to a second structure. Typically, you are only permitted one service... but you are permitted more than one set of service entrance conductors under certain conditions. We can get to that later if need be, but with the inspector saying you have to GEC each panel, I have to assume he is approving your two "feeder" scenario.

At this point, read 250.64(D) then come back with a better description of your arrangement and additional questions...
 

ArcLazerbeam

Member
Location
VT
It looks like you'll have to get a better grip of Code speak (terminology) first, then elaborate on what you have. In your opening post you said you have a 4-gang meter pack. Is that with or without mains. By mains, I mean service disconnecting switches and overcurrent protection, which can be in the form of fused switches or breakers. If this is the case then your use of the term feeders to garage is correct. Otherwise, they are service conductors.

Typically, you are only permitted one feeder to a second structure. Typically, you are only permitted one service... but you are permitted more than one set of service entrance conductors under certain conditions. We can get to that later if need be, but with the inspector saying you have to GEC each panel, I have to assume he is approving your two "feeder" scenario.

At this point, read 250.64(D) then come back with a better description of your arrangement and additional questions...
Thanks for pointing me in a new direction. I am aware of the terminology at least for the most part, and I do indeed mean feeders in this case. I agree it's not very common that you'd have two feeders to a second structure but this is where I am at. I'll re-read 250.64(D).
 

dionysius

Senior Member
Location
WA
Not common because in many cases it is an NEC violation to have two feeders supplying one structure.

What is the reason you have two?
Multiple customers in one building demands separate feeders/metering. Is this applicable here???
 

jaggedben

Senior Member
Multiple customers in one building demands separate feeders/metering. Is this applicable here???
Somewhat remarkably to me, 225.30 doesn't mention metering explicitly as a reason to have more than one supply. However you might be able to argue for 'different uses' under 225.30 (D), if someone made an issue out of it.
 

Smart $

Esteemed Member
Location
Ohio
Somewhat remarkably to me, 225.30 doesn't mention metering explicitly as a reason to have more than one supply. However you might be able to argue for 'different uses' under 225.30 (D), if someone made an issue out of it.
And I say what he has there qualifies. If the meter pack didn't have the service disconnects, he could have run two sets of service entrance conductors to the garage.
 

Smart $

Esteemed Member
Location
Ohio
And I say it is an AHJ call, I doubt it would fly here.
At the very least, it does qualify for the argument. AHJ approval is only required in the general sense, i.e. 225.30(D) does not say special permission is required like 225.30(B).

Let's see. On one hand, we have Code that says more than one feeder/branch circuit is permitted for control of outdoor lighting. On the other hand, we have separate metering of sublet property. IMO the latter should fly anywhere.
 

MasterTheNEC

Host of ElectricianLIVE.com
Location
McKinney, Texas
Occupation
Master Electrician & Director of Codes and Standards
Hey guys, question of the day. I'm doing a detached garage that will have two feeders going into it (House panel, and living space above garage.) This is all fed from the same service which is a 4 gang meter pack on the duplex, each feeder has its own 2" pvc. There's going to be a UFER once they pour the footer. However the state inspector is telling me I have to hit both panels with the GEC unbroken to UFER, I've never done a set up like this. Where is he getting this from?
As much as I hate to say this, I agree with IWire.:lol: I have seen the "Difference Characteristics" used in many cases but I doubt you would be successful on this one. However, give it a shot. Appeal to their sense of "labeling" at each location and who knows. However, it is not what I think of as acceptable uses for "different uses" but again speak with your AHJ and you just might be successful.
 

MasterTheNEC

Host of ElectricianLIVE.com
Location
McKinney, Texas
Occupation
Master Electrician & Director of Codes and Standards
Actually I would also go locked and loaded with (E) also ...Can't hurt to appeal to their desire to label everything.

(E) Documented Switching Procedures. Additional feeders or branch circuits shall be permitted to supply installations under single management where documented safe
switching procedures are established and maintained for disconnection.

Nothing says it can't apply to your situation....we can imply it is for Campus Style situations...but has been argued successfully in the past with simple labels at each location and at the main panel supplying the detached structure. The label detailed a documented safe shut down procedure....just sayin.


 
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