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New NEC code makes it impossible for DIY systems to be compliant

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FilterGuy

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I was just researching the NEC and stumbled on something I did not know.

https://www.ul.com/news/2020-nec-addresses-electrical-safety-what-code-officials-need-know

Also, Section 706.5 has been revised to simply state that ESS are to be listed. This is a significant change because now an ESS must be listed as a complete energy storage system and is no longer permitted to be made up of a field assembly of listed components.

Most of our DIY systems were not going to be 100% compliant anyway, but this sounds like it makes it impossible for a DIY to build an NEC compliant battery system... Is this other folks understanding as well?

For the most part I have learned that the NEC makes rules for good reason, but this sure feels like they were influenced by the makers of complete systems.
 
Ouch. It took some time for one of my local jurisdictions to adopt the RSD standards although that turned out to be easier than this will be in order to be compliant. I can still get a permit for my Skybox but only with solar and no storage.

Speaking of big corporations, the recent acquisition of Outback Power by Enersys and the acguisition of Pika by Generac are both strategic in terms of seeing this regulation coming. It was probably years that these regulations were in discussion mode.
 
.......
Until the Lobby is eliminated, capitalism is dead.
I am more optimistic than you. The fact that capital is flowing into the storage market means there will be plenty of competition for the big public utilities. Personally I am pissed that my hobby is going to get more complicated, but I can deal with that. I do see a lot more options for a lot more people to reduce their reliance on the grid.

There is still plenty of market competition around the globe and events of the last thirty years has seen this world dominated by capitalism. The fall of the USSR, the opening up of China and the increasing productivity of other parts of Asia including India. To be sure there are authoritarian regimes but the underlying economies are capitalistic.
 
It sounds like they removed the phrase that section 706 only applies to DC systems greater than 60 volts and replaced it with 'greater than 1kwh', and added the listing requirement, and made it applicable to stationary and mobile installations.

That would mean that if you put two Battleborn batteries together as your energy storage system, your not in compliance.

Banging head against wall.?‍♂️
 
Wow, that sounds like a shitty rule on the face of it. And its natural to wonder if influence from Tesla and other corporations in that space played a role in the rule. On the other hand I don't want to jump to conclusions. People are too quick to do that these days.

It would be easier to give the benefit of the doubt if not for the changes that @hankcurt points out. "greater than 1kWh" seems like an arbitrary and ridiculously low limit. I could maybe understand if it applied only to systems over a certain voltage (like the current 50V / 60V rule).

Anyone know anything about the code adoption process? Is the 2020 code set or is this a draft that could still be altered?
 
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I am not ready to give up on democratic capitalism either. There is no better system..... but like all systems it can be corrupted.

Back to my original statement:
" For the most part I have learned that the NEC makes rules for good reason, but this sure feels like they were influenced by the makers of complete systems."

Since I posted that statement I searched a little to find more information on why this change was was made and have not found much. However, I have come to see some logic to it. As we all know, these systems are just that: Systems. You can easily take a set of listed components and build a very bad and dangerous system.... just one wrong setting can make a big problem.

If you dig down into the wording of the code, It is possible to build a system out of the same listed components us DIYers might use. In fact, it can even be built in the field (Field Wiring). However, the total design must also be listed in order to be code compliant.

The NEC was faced with a problem where it was extremely complex for them to specify all of the parameters of a system in a way that a local code-compliance officer could verify. Consequently, they chose to move the system design (and listing) up stream from the installation. Now the code-compliance officer just needs to look for the system listing and does not have to check all of the parameters of the system.

So....I understand what likely happened and I may have been too quick to assume improper influence. I might even agree that it makes good sense. (I have met my local electrical inspector and I can assure you he would have no clue what to make of the simplist battery system I have built.) However, it still is irksome to me that I can't make a system that is to code no matter how safe it is.

The energy storage field is in it's early days and things are changing rapidly... consequently the NEC is playing catch-up and every new version of the code is getting big changes in the solar and storage area. Unfortunately, I don't see this slowing down anytime soon, particularly in storage.
Perhaps over time more industry standards will come into play and things will become more plug-n-play. (This is in the capitalistic interest of the various component makers) Till then the NEC is dealing with the wild-wild west.
 
BTW: I should know better than to jump to conclusions like I did. When the 2017 NEC 'Rapid Disconnect' rules first came out I thought they had gone too far.... but over time I have come to understand the reasoning behind rapid disconnect and can't really create a strong argument against it that does not include something like "I don't care about danger to firefighters'. Consequently I can accept it even if I don't like it.

The National Fire Protection Association is the author of the NEC and they are NOT a government organization (I think I heard someplace that they don't even get government funding)..... and that is probably a good thing. So far they seemed to have stayed away from the corruption that happens so often in government. Since they have so many members that are also competitors with each other it is probably a lot harder for a company or even a group of companies to exert improper influence.
 
I guess I have a problem when the line of demarcation goes from "You have to do it safely" to "We aren't going to let you do it yourself."

The NEC definitely exists for good reason. If you look at electrical installations from 60 to 100 years ago, they were just accidents waiting to happen. But when a regulator says that I can't do something because they don't understand it, they are basically saying I shouldn't be a hobbyist or a creator or a producer, I should just be a consumer.

There are plenty of hobbies that have the potential for danger. The custom car modification hobby is one of them. But they don't say you can't do it. Instead, they publish the standards that any roadworthy vehicle must meet.

Many of the great tech corporations that exist today started in someones garage or basement with people taking existing parts and putting them together in new ways to accomplish new things. I would love to own a Tesla, but I won't until Musk stops being a hypocrite about right to repair. He put his first car together from existing components that those manufacturers allowed him to tinker with, and now he does everything in his power to stop people from tinkering with the products he manufactures.

So yeah, this particular change bothers me because they left very little carve out for the DIY crowd. The previous 60 volt limit allowed for hobbyist to have room to create. In my opinion it was much more balanced.
 
Occam's Razor
A) Conspiracy by battery manufactures that don't have lobbies, very little margin, and won't work together,
B) Number of fires from DIY battery systems by people who watch videos and didn't use the correct gauge wire or have adequate breakers.
 
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I guess I'll be a rebel. I've always planned on doing my batteries/ESS after the solar installation passes inspection. Having an inspector show up to do a follow-up check on a system is unheard of here. I'll accept the risk of burning down my house because of my batteries/ess and having my insurance company deny my claim.
 
Maybe if I didn't call the building department and ask about UL batteries I could be a rebel too.
I'm paying $850 including shipping for UL listed batteries. And they aren't going to waste.
 
Maybe if I didn't call the building department and ask about UL batteries I could be a rebel too.
I'm paying $850 including shipping for UL listed batteries. And they aren't going to waste.
I believe you've needed UL listing on batteries since NEC 2017. The 2020 ruling seems to say you need system certification rather than component certification (e.g., a battery is a component of an ESS).
 
My permit paperwork is going in this week. We'll see how it goes.
The official battery specs are part of the permit package.

I can still cancel my system. I would rather not.
 
This is how it starts.

And this is the very reason I was flamed in another thread for calling out the previous generation for putting our country in the dire situation it's in. One's argument was "And is the profit motive a bad thing?" It's appalling how little people know about economics and history. This is hardly the forum to go into this subject with people and frankly, as old as the members are who expressed their disapproval of what I said, they should know this stuff by now, and therefore I have neither the time nor patience to educate them. But here's some food for thought:

Big corporations write anti-competition laws under the guise of "Regulations". These are paid for in the Lobby, where politicians are bought off to pass them as law, enforced by a gun held by the government. These laws then present a barrier of entry for new businesses/competition, and constrict already existing smaller corporations and businesses over the long term, eventually until they either give up and are acquired by the larger corp. (via another anti-capitalist mechanism of mergers and acquisitions), or the more defiant businesses ultimately fold into bankruptcy by being priced out of the market by the larger corp. over time, as the larger corp can absorb loss for a longer duration than the smaller business. Since these "Regulations" are .gov enforced, the big corps. involvement stops at the lobby, and taxpayers (you) now get to fund big corporation's anti-competition, anti- capitalist, anti-American regulations! You personally, are literally funding fascism, the protection of big corporations from competition, and the decimation of small business all while the barrel of a gun is pointed at your head! Neat, right!

This process is fundamental fascism, and diametrically opposed to capitalism. Big corporations are self-serving only, are only interested in profit and smashing competition, and screw everyone else.

See how that works?
Regulations and building codes protect people living in buildings. Construction contractors have every incentive to cut corners since the goal of capitalism is to maximize profit.
 
Regulations and building codes protect people living in buildings. Construction contractors have every incentive to cut corners since the goal of capitalism is to maximize profit.
I agree that codes are supposed protect people. But big business puts a lot of effort into manipulating the codes.
Big business has been taking over everything.
 
I signed up for the free access to the NFPA codes at https://www.nfpa.org/Codes-and-Standards/All-Codes-and-Standards/Free-access

I think the result of these changes will largely depend upon your code enforcement AHJ. The language in article 690 defines the parts of a photovoltaic system and it shows the ESS (electrical storage system) as separated from the PV and inverter.

Article 706 says that an ESS may include a charge controller or inverter, but also states it doesn't cover uninterruptible power systems (which obviously contain a charge controller and inverter), and the differentiation appears to be if the batteries are used to normally power the system or are only used to power the system during a power failure.

Then there is article 480 on storage batteris, which requires storage batteries to be listed unless they are lead acid batteries (so a little fear of the unknown here). This article might be useful to people assembling battery packs as it covers terminal connection practices, corrosion, conductive battery cases and voltage drop requirements. So even if it doesn't apply to you, it might steer you towards best practices. So how do you know if you have a PV system with storage batteries or an ESS system? I think article 690 leans towards calling batteries connected to a PV system an ESS, but depending upon the complexity of your system, you might be able to call them storage batteries.

Also, article 706 on electrical storage systems goes still goes into all the detail of how an ESS has to be constructed (disconnects, over current protection, wire ampacity, etc.), so might your AHJ say the ESS system listing applies to manufactured systems, but the method of construction and parts requirements apply to DIY constructed systems. I suppose it will depend on their attitude and level of interest.
 
Well Im using mpp units, so im not totally code accurate anyway.

There is buildings with 80s AL wiring still operating just fine. Staying safe is relative.
 
People becoming grid independent is the last thing the .gov wants.
I am more optimistic. It also depends on which government you are talking about. I hear rumors there may be a new government soon in Washington. Out here on the left coast, California is subsidizing the cost of batteries in an effort to make the grid more resilient.
I am still going to take the Federal Tax credit and pull a permit from my local building department under the old rules ASAP. My next project may have to be in an RV.
 
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I think the result of these changes will largely depend upon your code enforcement AHJ.
Thats good input. In California the AHJ for prefabricated homes is the state government. There has recently been an increase in people putting these into their backyard as accessory dwelling units. Otherwise known as mother in law units they are also used as VRBO or AirBNB short term vacation rental units in areas like mine where there is a lot of tourist visits. When one door closes, another one opens.
 
Maybe if I didn't call the building department and ask about UL batteries I could be a rebel too.
I'm paying $850 including shipping for UL listed batteries. And they aren't going to waste.
The batteries are probably "UL Recognized".
Close but no cigar?

Obviously lithium batteries can make it relatively easy to start a fire.
Ideally we'd get to the point where there is a standard for a lithium cell (or bank of cells), that both BMS and cells are listed as meeting.
Then we could mix & match within those. There should just be parameters of the cell to be entered in the BMS.

Is an ESS a battery together with charge controller? And with inverter? Or just a stack of lithium cells with BMS?
Is a bank of of AGM (or FLA) an ESS? it doesn't require a BMS.
 
Is an ESS a battery together with charge controller? And with inverter? Or just a stack of lithium cells with BMS?
Is a bank of of AGM (or FLA) an ESS? it doesn't require a BMS.


From NEC 2020 article 690 - PV system, the ESS doesn't include the inverter
1607884829731.png




From NEC 2020 article 706 - ESS might or might not include the charge controller and inverter
1607884646259.png
I think there are too many design variations to make an all encompassing statement.
 
The batteries are probably "UL Recognized".
Close but no cigar?

Obviously lithium batteries can make it relatively easy to start a fire.
Ideally we'd get to the point where there is a standard for a lithium cell (or bank of cells), that both BMS and cells are listed as meeting.
Then we could mix & match within those. There should just be parameters of the cell to be entered in the BMS.

Is an ESS a battery together with charge controller? And with inverter? Or just a stack of lithium cells with BMS?
Is a bank of of AGM (or FLA) an ESS? it doesn't require a BMS.
You are correct.
I'll mention it to AltE. If no cigar I'll have to go with Bob's plan.

It would be nice for the pre approval to go smooth.

I'll get through it even if I have to buy a NEC 2020 Article 690 approved ESS. ?
 
I'll get through it even if I have to buy a NEC 2020 Article 690 approved ESS. ?

Then you'll have to install an explody lithium battery instead of an (almost) intrinsically safe AGM.

I suppose either LiFePO4 or AGM, if severely abused electrically, can become a fire hazard.
(but so can a piece of copper wire, ergo fuses/breakers with sufficient AIC rating.)

Maybe my solution would be to connect four, 20A 12V batteries in series and wire that to my 23 kW of Sunny Island.
Perhaps I would park a golf cart or forklift nearby. With an Anderson connector (or four) for charging the batteries, of course.

The "batteries optional" hybrid inverters may be the easiest to install and get permitted with a wink.

Another way would be an automatic transfer switch with plug for generator.
And maybe a car with V2H in the driveway.
 
Ideally we'd get to the point where there is a standard for a lithium cell (or bank of cells), that both BMS and cells are listed as meeting.
And I would add that there needs to be some recognition of fire risk between chemistries. In other words Lipo should not even be considered unless housed in a concrete bunker. NCA and NMC need to have mitigation like in Tesla Powerwalls and other UL approved types. LFPs can have a different standard. The thing that is ironic is the lack of rules around Pb chemistries some of which do give off explosive hydrogen gas.
 
I think most of our lithium batteries are pretty safe.
I see a lot of systems with old corroded 12V lead acid batteries that don't look very safe.
And people using way too many amps on 12V systems.
 
Solutions are beginning to emerge.
I am not sure if you mean solutions for the DIYer or solutions in the broader market.

It is is always the case that when code changes solutions start showing up in the market. In fact, I have never seen a code change that did not have at least one solution (all be it an expensive solution). The various suppliers have a capitalistic interest in providing solutions. Over time the incremental cost of the new code tends to go down as the competition increases.

Unfortunately, the NFPA has no interest or incentive to address the DIY market. However, solutions for the larger market typically have beneficial trickle-down to the DIY market.


Then you'll have to install an explody lithium battery instead of an (almost) intrinsically safe AGM.

I suppose either LiFePO4 or AGM, if severely abused electrically, can become a fire hazard.
(but so can a piece of copper wire, ergo fuses/breakers with sufficient AIC rating.)

And I would add that there needs to be some recognition of fire risk between chemistries. In other words Lipo should not even be considered unless housed in a concrete bunker. NCA and NMC need to have mitigation like in Tesla Powerwalls and other UL approved types. LFPs can have a different standard. The thing that is ironic is the lack of rules around Pb chemistries some of which do give off explosive hydrogen gas.


Yes, this goes to the broader issue I have seen: All lithium chemistries are lumped under the "They can explode" category. (Example: LiFePo4 is considered just as dangerous as any other lithium chemistry for shipping) Hopefully over time they will start differentiating between the chemistries, but it might be a while. (It is kinda like "anything with the word nuclear is horrible horrible Horrible....." That is why they changed the name of Nuclear Imaging to Magnetic Resonance Imaging or MRI)
 
The "batteries optional" hybrid inverters may be the easiest to install and get permitted with a wink.
That is my fallback plan.
Another way would be an automatic transfer switch with plug for generator.
And maybe a car with V2H in the driveway.
I have been skeptical of V2H in the past but this new development has changed my perspective. I also like the idea of a hopped up golf cart with 48 LF 280s. Or an electric tractor.
 
That is my fallback plan.

I have been skeptical of V2H in the past but this new development has changed my perspective. I also like the idea of a hopped up golf cart with 48 LF 280sn. Or an electric tractor.
People drive golf carts all over in Florida. They're legal on the streets in a lot of towns.
And people have high dollar golf carts. lol
That tractor would probably need wheelie bars.
 
I am not sure if you mean solutions for the DIYer or solutions in the broader market
A little of both as discussed down thread. I am hopeful as this gets better defined and as overall battery manufacturing capacity increases that the cost of "UL approved" ESS devices comes down. There will always be a price difference between UL approved and commodity devices like we have seen in the inverter market.
 
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