solar with the 6 switch rule

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SunFish

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Does a backfed breaker count as one of 6 max service disconnect switches when it is only a utility interactive grid tied inverter? (no batteries)
 
I'm working on a job that has 6 main service breakers in a panel that is completely full. We can backfeed a sub-panel, plenty of room and meet all requirements of the 120% rule. Just not sure if the addition of the inverter breaker would count as a 7th service disconnect.
 
SunFish said:
I'm working on a job that has 6 main service breakers in a panel that is completely full. We can backfeed a sub-panel, plenty of room and meet all requirements of the 120% rule. Just not sure if the addition of the inverter breaker would count as a 7th service disconnect.
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That varies greatly by AHJ, so we cannot answer that for you.
In some places you can even add up to six PV AC disconnects if you can justify that many separate systems.
In other places you cannot add even one if you already have seven.
 
GoldDigger said:
That varies greatly by AHJ, so we cannot answer that for you.
In some places you can even add up to six PV AC disconnects if you can justify that many separate systems.
In other places you cannot add even one if you already have seven.
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Six?
 
SunFish said:
I'm working on a job that has 6 main service breakers in a panel that is completely full. We can backfeed a sub-panel, plenty of room and meet all requirements of the 120% rule. Just not sure if the addition of the inverter breaker would count as a 7th service disconnect.
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If you're backfeeding a subpanel with a load side connection, then no, that doesn't count as an additional service disconnect. If your AHJ tried to count it, that would be an interpretation I don't believe any of us have ever heard of.

The controversy is over whether it counts if it's connected directly to the utility supply like the other service breakers. If that's the case, then ask your AHJ.
 
jaggedben said:
If you're backfeeding a subpanel with a load side connection, then no, that doesn't count as an additional service disconnect. If your AHJ tried to count it, that would be an interpretation I don't believe any of us have ever heard of.

The controversy is over whether it counts if it's connected directly to the utility supply like the other service breakers. If that's the case, then ask your AHJ.
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He said "6 main service breakers in a panel that is completely full", which implies to me that the main panel is MLO. He could backfeed a breaker in a sub fed from a breaker in the main and it would be a load side connection; the only panel where the 120% rule would apply would be in the sub.
 
ggunn said:
He said "6 main service breakers in a panel that is completely full", which implies to me that the main panel is MLO. He could backfeed a breaker in a sub fed from a breaker in the main and it would be a load side connection; the only panel where the 120% rule would apply would be in the sub.
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Isn't that what I said? :cool:
 
SunFish said:
I'm working on a job that has 6 main service breakers in a panel that is completely full. We can backfeed a sub-panel, plenty of room and meet all requirements of the 120% rule. Just not sure if the addition of the inverter breaker would count as a 7th service disconnect.
Click to expand...

A PV breaker in a load side sub-panel is not counted as a service disconnect.
 
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