What happens when you want to remove your roof solar panels?

[madsci1016]

Wow ok, first I was like "micro inverters are stupid it's way cheaper to just buy one big inverter" Then I learned about the new codes for rapid shutdown 2019 and on requiring a optimizer at every panel now and it's like there no choice BUT micro-inverters now.

Sigh. This is why codes suck.

[where2]

Codes have a purpose in life, it's to keep your neighbor from torching their house because they DON'T know enough about electricity to make sound decisions.

A three line diagram is literally what it sounds like: (If you can read and write schematics, you can write a 3-line diagram. Based on your holiday light show, I think you can probably handle this). L1, L2, Neutral, and Ground each are shown as a line from the furthest micro-inverter all the way to the main electrical panel that the PV system will connect to. Every stop or connection you make along the way is detailed out with the make & model of the thing.

In my case, I showed the PV panels (listing their manufacturer, model number, wattage). Then I showed the + and - wires that connect to the micro-inverter. I showed the micro-inverter as a smaller rectangle with the Enphase, M215-60-2LL-S22 designations. At that point, I start showing 4 wires and wire gauges (L1, L2, N, Gnd). When I go through a connection point or junction box, I list out the manufacturer and model of the box. If I hit a circuit breaker, I list out the current rating for the breaker, and whether it is single pole or a double pole breaker (they're double pole). Also show the "wiley" WEEB washers that ground the panel frames to the roof rack. Each segment of roof rack needs a jumper to connect the rack electrically to the next piece of adjacent racking. Show the continuous bare ground wire that grounds each piece of the rack to your ground rods (that wire being continuous without breaks is SUPER important). Make sure you show two 8' ground rods spaced at least 8 feet apart. Your existing home electrical system may currently only utilize a single ground rod, now is your chance to upgrade to TWO ground rods since the latest NEC code requires two rods. In my three line diagram, I also listed voltage drops expected based on the maximum potential current being generated by the system and the length of the wire to the next thing. I drew it all on 11x17 paper in Autocad, because I draw in Autocad everyday as my main means of sustainable employment.

Above was just the "electrical" diagram, and since you're in Florida, you have to submit that 3-line diagram to FSEC in Cocoa Beach along with a check for $250 or whatever the latest design review fee now is. FSEC will review the three line diagram for NEC compliance, since the FL legislature doesn't seem to think each individual municipality has the thorough understanding of the NEC necessary to review PV systems and determine whether they are NEC compliant. (honestly, I'd rather converse with one person who does nothing but review PV system designs, then deal with explaining a PV system to a "Noob" at the local municipality.) When I submitted my first design, they responded with a phone call to suggest a minor design modification, and blessed my design when I incorporated their "hint". When FSEC gives you your certification number, you need that to carry to your local municipality or county (which ever has jurisdiction) and apply for your building permit. If you can get your hands on a copy of the latest NEC code book, it helps to understand what types of cables can be used where, and what things in a PV system need grounding. It's also a bit confusing reading the NEC, so review Mike Holt's PV grounding information online. I think I found slides from some seminars he had done in the past that were helpful. The whole section on PV systems in the NEC is good to understand so you know where to backfeed the energy into your main panel, and can have an intelligent conversation if anyone questions anything as you are installing your system.

Thanks to Hurricane Andrew, and numerous storms since, most FL municipalities will want some form of stamped structural engineering design that says the PV array won't rip the roof off in the event of a storm, or go flying through the neighborhood (if it's not attached to the roof). This is where you have to go out and employ a professional. In my case, I know someone who is a structural engineer (P.E.) who has a personal business in addition to being employed as a structural engineer. He's helped me with structural engineering upgrades to my house built in 1961. He did the math to determine that a 3 second gust of 170MPH would not rip the 4.4kW PV array off my roof, if I used 102 attachment points to the roof trusses. I still hope we never test that math, but that math and the liability associated with his math is worth $$ to a structural engineer. I paid him for his knowledge and the license he keeps with the state of FL. Having my own professional licenses to upkeep, and having taken college classes to get my own professional licenses, I don't hassle him about his "rates" when I need his expertise. The state deems me unfit to do the higher math necessary to determine wind load calculations, just as it deems him unfit to do what I hold licenses to do.

With those two documents described above, the FL PV Certification Number, and the PE structural design drawings, I was able to visit my local municipality and apply for a permit to install my own PV system.

When the inspectors came out for the "in-progress" and "final" inspections, they reviewed my permit documents (the 3-line diagram, I drew, and the structural engineer's drawings). They asked me where I was at in the install process, asked me to show them where this was or that was. They reviewed my install for obvious errors like bolts that didn't hit the rafters in the attic, electrical connections which were not NEC compliant or connectors that were not torqued to spec. With all that, at the end of my final inspection, the inspectors were impressed that I didn't cut any corners, or miss any
inspection points, considering I don't do this for a living. I think it's the fact that I "dont' do this for a living" that keeps me from overlooking things trained pros who do this every day may overlook. I treated the NEC like a textbook, learning what I could reading it, and asking questions when it seemed confusing. In my case, my municipality will take questions during two periods each day. When it came to labeling the panels, I went to my municipality and asked precisely which labels they wanted on which panels, because the NEC simply said "electrical panels energized by PV must be labeled appropriately" or some other generic language. I said "here's the decals I found online for PV panels, which decals do you want where?" and the staff were helpful in picking what they wanted to see on which electrical panel as well as explaining why. When the inspectors (one for electrical, one for structural) came out for the final inspection day, the panels had their warning labels and I was able to explain why each panel was labeled with a specific decal.

You are correct, I'm NOT in the panhandle. I moved back south when I finished my studies at UF, because it got below freezing in Gainesville. You can tell the seasons change when the license plates change color down here, that's about it. I know some good folks who live in the panhandle, but I am a native from SoFL.

[madsci1016]

I'm used to a 3-line or 1-line diagram referring to 3 phase power diagrams, hence the question. I'm assuming one diagram shows both AC and DC sides of the system?

I grew up in Fort Lauderdale, job out of college brought me to Panama City. Wife from Miami would much rather be back down there.

Are you going micro inverter for your new system? Seems like the code change starting January of this year pretty much forces you to go that way. As it's now cheaper to do $130 micro inverter per panel than a large $1800 inverter plus $80 rapid shutdown module per panel. (EDIT, NVM, looks like you said you went micro with the first system anyway).

I've never dealt with getting permits before. I am in red-neck ville, so they might not have started the "we need structural diagrams" yet if that is not a state wide thing. I'm guessing I just need to ask them that? Only solid info I got so far is the power company, Gulf Power (now owned by FPL anyway) wants to see the electrical permit, but don't need to see any structural (makes sense).

I found this site, is there an merit to it's services? https://get.solardesigntool.com/feat...rmit-packages/

[where2]

Originally Posted by madsci1016

I've never dealt with getting permits before. I am in red-neck ville, so they might not have started the "we need structural diagrams" yet if that is not a state wide thing. I'm guessing I just need to ask them that? Only solid info I got so far is the power company, Gulf Power (now owned by FPL anyway) wants to see the electrical permit, but don't need to see any structural (makes sense).

I found this site, is there an merit to it's services? https://get.solardesigntool.com/feat...rmit-packages/

The merit to the services offered is like anything else: what's your time worth? Plenty of places offer PV permit package services, including Renvu where I ordered my last panels. From my point of view, my time to assemble my own permit package, and familiarity with the system involved, leaves a lasting memory of how the system works, which comes in handy when you have to troubleshoot something in the future.

Simplest way to find out what the permit package will need to include is to contact the local Authority Having Jurisdiction (AHJ) and just ask. When I started down this rabbit trail, I didn't realize every system in FL had to pass through the design review of FSEC. My local building department is the one who said "to install any PV system, it needs to be a certified system." When I googled it, and read FSEC's purpose in FL, it all started to make sense. Then I read up on what FSEC wanted in their review package, and built a set of drawings that met that criteria. Once I had an FSEC certified system design, I quizzed the local building officials what they wanted in their permit package in addition to the electrical diagrams, data sheets and system certification documents? My building officials would much rather answer questions up front and receive a permit application with all the appropriate paperwork attached, than stamp "Permit Denied" on stuff and deal with upset customers who throw a fit when they find out their permit application was denied. As taxpayers, we ALL employ the staff in the local building department to fairly and justly apply the building code rule books to the construction trades. Making permits difficult to obtain does not "help" the intended goal of gaining a high degree of code compliance with the local adopted building codes to keep the public safe. Making permits difficult to obtain actually drives DOWN compliance with codes. Ideally, the permit package application process should be fairly easy if you have all the documents you need. If you wish to employ some service to assemble the documents for you, that's your decision, just as it is whether you employ a solar firm to install your system.

Before I plunked down an offer on a piece of real estate in rural Maine, I visited the local town office and discussed with the staff there what permits would be necessary for various potential projects I envisioned the place might need. Again, the staff were helpful just like the staff in my municipality in FL. They actually commented "that's a great question to ask, before you get your heart set on buying a place", and considering how varied different municipalities can be, it's an important question to ask before purchasing any property. My municipality in FL is actually known in the local construction trades as being "Difficult to work with". In my experience, they're only "difficult" when someone comes in claiming to know everything and to have been doing "XYZ" for the last 30 years and never had an inspection failed for "that". The building codes are an ever changing set of rules, contractors are required to keep up with them to maintain their contracting licenses. The building officials & building inspectors are left with the unfortunate task of playing referee in a game with moving rules and guys who make money by getting to the next game as quickly as possible. Pointing out code failures that may have once been legal, but are not presently legal in the building code costs contractors $$$, and that's why my FL municipality is termed "difficult to work in".

[NiHaoMike]

Originally Posted by madsci1016

Are you going micro inverter for your new system? Seems like the code change starting January of this year pretty much forces you to go that way. As it's now cheaper to do $130 micro inverter per panel than a large $1800 inverter plus $80 rapid shutdown module per panel. (EDIT, NVM, looks like you said you went micro with the first system anyway).

The shutdown switches can just be DC SSRs (not cheap, but less than $80 each) and a $20 PVAF-T2 takes care of the arc fault detection part.

An even cheaper way would be to use a DC rated switch or relay to short the string, but that would require all the panels to be able to withstand a constant short circuit.