City requirements for grid-tie

[ssjrapter]

I'm seeing up my solar system and know my city participates in net meeting, but I can't seem to find what the local city codes require of anything regarding how the things are required to be setup. Specifically in Oklahoma City if I actually need a manual transfer switch with my system or if I can just have it permanently attached to my inverter with grid backup, this bypassing the need for both a feeder tap and a tap breaker as well as a very bulky and expensive transfer switch. I understand the need for a fused disconnect and manual breaker just after the meter but I can't for the life of me figure out why I would need the inverter bypass to become grid tied.

 

[zanydroid]

You should have put the specific requirements in the post title.

For AHJ specifics I think it is smart and appropriate to ask in multiple forums (here, r/solar, local board or Nextdoor), that increases the chance of someone seeing it.

Did you call AHJ?

For instance I monitor Nextdoor for solar questions and will send my plans / multiple inspection
experiences

 

[zanydroid]

With regard to your post, it is a little confusing on the wiring specifics. Post SLD and photos of existing conditions. OR description of solar system type and capabilities.

For instance if it was pure grid tie system, of small size, I would expect a same AHJ to require minimal disconnect. Though some places require things like solar able to be disconnected externally without turning off the whole house.

 

[ssjrapter]

Shouldn't my AHJ have documentation on what the requirements are somewhere? It just feels like the source of truth on what the requirements are is "ask somebody" with the eventual conclusion being "trust me bro". Your think regulations would be available to point to like NEC or something else.

As for the system it will be a 18k eg4 with about 15kw of panels. Net metered using their documentation but it seems from reading in here the eg4 documentation literally covers all AHJs.

Essentially why do I need what is highlighted in this diagram of there water never plans to use the transfer switch?

 

[chrisski]

Unless a member is in OKC, has permitting experience, and is willing to share the details, you can’t trust any answer you get here.

As mentioned, when you contacted OKC, what did the say?

Are they NEC 2020 or NEC 2023, and what exceptions do they follow? Other than that, I don’t think they need to walk you through step by step.

I probably could have figured the maze of regulations and building out, but I would have taken two years. The contractor took five months, but there were 7 or 8 real days of work, and in between was waiting for approval to go to the next step.

On my AHJ, not only did the city got involved for electrical work, the fire dept also had to clear it?

 

[zanydroid]

Your think regulations would be available to point to like NEC or something else.

FWIW contractors know what the real rules are/what they can get with via experience and use this in their operations. You have to ask people to catch up. NEC can be ambiguous/leave discretion room.

Authoritative is AHJ establishes paper trail but they may not answer your questions / be ambiguous. Permit establishes paper trail too.

In my case I had plans from an existing grid tie system on my property (within one year of second one) and did not need EE stamp. I also carefully read POCO requirement and asked on Reddit/here how many people qualified for simplified disconnect POCO allows (the wording wasn’t super crisp on official documentation).

So I was confident in asking draftsperson on second plan to do it the same way as first system. It was approved that way by POCO and City and I installed to that SLD.

 

[zanydroid]

As for the system it will be a 18k eg4 with about 15kw of panels. Net metered using their documentation but it seems from reading in here the eg4 documentation literally covers all AHJs.

Essentially why do I need what is highlighted in this diagram of there water never plans to use the transfer switch?

That diagram is pretty good, but isn’t the only way to do it, also isn’t 100% accurate (depends on ambiguity, for instance it’s not necessarily a feeder tap, tap implies reduction in conductor size from the source side breaker; sometimes these wiring diagrams omit important stuff like EGC path, yet people take the omission as gospel/superseding NEC which they don’t know well as DIYers). If the diagram is given to an experienced contractor they would fill in the blanks.

So if you look at threads here, there are indeed people that replaced the $$$ bypass with a larger Polaris style connector with spare ports that they will swap house to (by redoing the wiring). They give up the convenience of the 200A bypass but save $1000 and space on the wall.

So you should do at least this to avoid screwing yourself if the inverter has problems.

If your AHJ has a “solar/storage must be bypassable without turning off house” rule the this bypass will satisfy. I do not know if simpler will satisfy. (Now sometimes the rules are not codified as local amendments, but these still need to be respected unless you want to get in a fight with the inspectors/plan reviewers. As well sometimes correct complex justification based on the written text is too hard to explain).