Line side or load side?

[wwhitney]

The section title and the preceding sentence both reference load side. You don't get to take that sentence out of context.

[Still devil's advocate] Yes, but what is the context? Is the context "equipment on the load side" or "systems with a load side connection"? As the latter may be considered to be all systems. [Unless you have a PV inverter with built-in AC breaker that is rated for use as service equipment, then I think you could argue nothing in that system is subject to 705.12.]

So if you take the context to be "systems with a load side connection" then you could reasonably interpret the term "distribution equipment or feeders" to include service equipment.

I.e. the AHJ's position isn't based on making something up or directly misreading something, just on a disagreement on context. If the second sentence instead said "Where load-side distribution equipment or feeders . . ." then you would be clearly right. But it doesn't say that, so it is open to the interpretation in the OP.

Cheers, Wayne

 

[jaggedben]

For starters, I've been having one or another version of this conversation with AHJs for ten years and it always seems like they intially are aware of the load side rules, and it's a revelation for them when you point out there's a separate section for supply side. So I strongly suspect that's the case here and that he is not parsing the language like only you do. ;-) Most AHJs know a little bit about each article in the code rather than having fully informed ideas about 705.

As far as your point, sure, every interconnected PV system involves both sets of rules, even if the supply side consideration is basically inconsequential when there's one service disconnect feeding a single main panel. But that doesn't change which rules apply where. The section titles make that clear. If we can't rely on section titles to limit scope of application then a large amount of practical code interpretation becomes completely infeasible. I'd only add that, yes, the language could almost always be improved to reduce confusion. But the AHJ is still wrong. And probably just because he's relatively green on this section.

 

[Another C10]

If I may .. what is the advantage if any in connecting a PV system to the unprotected side of utility as apposed to the breaker protected side of the utility power.

 

[electrofelon]

If I may .. what is the advantage if any in connecting a PV system to the unprotected side of utility as apposed to the breaker protected side of the utility power.

more capacity. Because of the "120% rule" we are typically limited to a 40 amp back fed breaker on a 200 amp panel. A supply side connection is still protected, it's basically just the same thing as using 230.40 exception #2 to add another set of service conductors and service disconnect which then serves the PV.

 

[jaggedben]

If I may .. what is the advantage if any in connecting a PV system to the unprotected side of utility as apposed to the breaker protected side of the utility power.

There's no general reason. It just may be more cost effective in some situations after considering the rules and the existing equipment.

 

[ggunn]

There's no general reason. It just may be more cost effective in some situations after considering the rules and the existing equipment.

There's no general reason but there may be a bunch of project specific ones.

 

[pv_n00b]

It's been a common point of discussion if the PV system disconnect on a supply-side interconnection is also a service disconnecting means. There are some good arguments that go either way and heavy hitters on both sides. From what I have been hearing, the 2023 NEC is going to clear this debate up and come down hard on one side. We will see.

 

[ggunn]

It's been a common point of discussion if the PV system disconnect on a supply-side interconnection is also a service disconnecting means. There are some good arguments that go either way and heavy hitters on both sides. From what I have been hearing, the 2023 NEC is going to clear this debate up and come down hard on one side. We will see.

INCOMING!!!

 

[electrofelon]

I. From what I have been hearing, the 2023 NEC is going to clear this debate up and come down hard on one side. We will see.

If that happens, then what's the total tally on how long it took them to clear that up???? Jeepers, the NFPA is worse than the government....

 

[pv_n00b]

If that happens, then what's the total tally on how long it took them to clear that up???? Jeepers, the NFPA is worse than the government....

The results of having to use volunteers to make code and incorporating public input. It makes everything take a long time. What's really interesting about this particular change is that it was kicked off by a battle between CMPs using proposed changes as ammunition.