705.12 A

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jbuzz

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Would a panel used as service equipment that is installed as main lugs be considered on the supply side of Service disconnecting means as it pertains to this code. Basically I have a 100 Amp service with a 4 space load center directly below the meter, the premises are fed by a 2-100 breaker and I used the other two spaces to feed/backfeed a Utility interactive system. Now the inspector says i have to comply with 705.12 (D). I disagree but figured I would take it up with you guys.
 
jbuzz said:
Would a panel used as service equipment that is installed as main lugs be considered on the supply side of Service disconnecting means as it pertains to this code. Basically I have a 100 Amp service with a 4 space load center directly below the meter, the premises are fed by a 2-100 breaker and I used the other two spaces to feed/backfeed a Utility interactive system. Now the inspector says i have to comply with 705.12 (D). I disagree but figured I would take it up with you guys.
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If it is on the load side of the disconnecting means then you should be good.
 
jbuzz said:
Would a panel used as service equipment that is installed as main lugs be considered on the supply side of Service disconnecting means as it pertains to this code. Basically I have a 100 Amp service with a 4 space load center directly below the meter, the premises are fed by a 2-100 breaker and I used the other two spaces to feed/backfeed a Utility interactive system. Now the inspector says i have to comply with 705.12 (D). I disagree but figured I would take it up with you guys.
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I am having a really hard time understanding your situation. Can you clarify? photo or sketch is best.

Right now it does seem like you have a "split service" panel. Ie two @ 2 pole breakers can be installed, and each would be a service disconnect, NOT load side breakers. In your case, one @ 2pole 100 Amp breaker feeds the house and you installed the PV breaker in the other space. If there is no breaker between this PV breaker and the meter then it certainly does sound like a supply side connection. By "between" i mean no breaker feeds this pv breaker, although physically the 100Amp breaker may very well be sitting on the busbar adjacent to the PV breaker......
 
Where you have service conductors on one side of a breaker and the GTI conductors on the other side, you have a 705.12(A) installation.

In this case, the MLO panel busses are considered service conductors.
 
Exactly the way I see it, but he did insist that because its point of connection is in a panel board I would have to comply with 705.12 (D) and would have to use the 120% rule on the buss, which is totally pointless because there is no way of the buss being overloaded to begin with.
 
jbuzz said:
Exactly the way I see it, but he did insist that because its point of connection is in a panel board I would have to comply with 705.12 (D) and would have to use the 120% rule on the buss, which is totally pointless because there is no way of the buss being overloaded to begin with.
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Well....:p OK...let's run with what the inspector wants.
You do, in fact, meet the 120% rule. Very, very handily.

120% rule says ,
The sum of breakers SUPPLYING power to the busbar cannot exceed 120% of the busbar rating, right?
What is that sum?
Well... you do not have a breaker supplying power from the utility side
and
you have your PV breaker supplying power to the busbar from the other side...
so your sum of breakers is ...your PV breaker.
still WAY under the busbar rating. Probably don't even need teh 120% allowance.

(assuming your pv breaker Amps is less than the rating of the bus. The bus i guess is at least 100 amps given that you have another 100A load breaker fed from it.)
 
Zee said:
Well....:p OK...let's run with what the inspector wants.
You do, in fact, meet the 120% rule. Very, very handily.

120% rule says ,
The sum of breakers SUPPLYING power to the busbar cannot exceed 120% of the busbar rating, right?
What is that sum?
Well... you do not have a breaker supplying power from the utility side
and
you have your PV breaker supplying power to the busbar from the other side...
so your sum of breakers is ...your PV breaker.
still WAY under the busbar rating. Probably don't even need teh 120% allowance.

(assuming your pv breaker Amps is less than the rating of the bus. The bus i guess is at least 100 amps given that you have another 100A load breaker fed from it.)
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And the effective OCPD of the POCO service conductors supplying the panel is very likely much more than the busbar rating, no matter now big it is relative to the nominal service amperage. So the PV backfeed is not making much of a difference at all. :)
 
I concur that as described this a supply side connection, and no part of 705.12(D) applies. The couple times that I've had to argue with AHJs about this they have come around when I used Zee's line of logic (there is no utility breaker to add to the sum).
 
Still arguing the article that applies to this situation, I was forced to go over the inspector and still keep having 705.12 D thrown in my face, I am going to continue to fight this if I have to go all the way to the state electrical board.
 
When it says may be permitted to be connected to the load side of the service disconnecting means of the other sources at any distribution equipment on the premises.
Does this mean you cant connect to the load side of the service disconnect but at equipment fed by the service
 
electricalist said:
When it says may be permitted to be connected to the load side of the service disconnecting means of the other sources at any distribution equipment on the premises.
Does this mean you cant connect to the load side of the service disconnect but at equipment fed by the service
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No...

It means you can connect anywhere on the load side of the disconnecting means of any other source (including the service disconnecting means)... subject to the provisions stated therein.
 
Thank you for the Ammo

Thank you for the Ammo

Thanks Guys Much appreciated Articles, they are exactly what I needed. I've sent them and the powers that be will be reviewing them soon.
 
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