There is a large misunderstanding about lithium battery LVD voltages vs type.
Simpliphi for example has a very high LVD at between 24-25v depending on DOD you want. And thats true, the VFX/FX you can’t set the LBCO that high so you have to get creative. Vs most of the better prismatic cells, at around 20-21v LVD ( which is all I use) Which every legacy inverter I know of has a higher LBCO set point than that. Jay > On Sep 18, 2024, at 7:22 AM, Mac Lewis via RE-wrenches > <re-wrenches@lists.re-wrenches.org> wrote: > > Hi David, > > This upgrade comes up a lot. You are at a point where you have to decide; do > I match my old equipment with a new 24V Lithium battery bank (thus limiting > my battery bank options), or do I upgrade my equipment to 48V which opens up > the brands available? > > I have had good success matching older equipment with new batteries but my > preference is always to try to get these systems to 48V if it's financially > viable. Ray describes a solution to get the LBCO high enough to shut off the > inverter before the BMS shuts down and this works. You can also hardwire a > power supply to wake up the BMS directly from the generator. > > Remote monitoring is very useful too, especially in a rental scenario like > this. It may be time for a full upgrade. > > Very hard to know which companies will make it through... > > > > On Tue, Sep 17, 2024 at 4:01 PM Jason Szumlanski via RE-wrenches > <re-wrenches@lists.re-wrenches.org > <mailto:re-wrenches@lists.re-wrenches.org>> wrote: > I don’t want to stray too far off track, but it’s worth discussing how > challenging it is to predict which manufacturers will be around in a few > years. > > I know this might be a touchy subject, but Enphase is beginning to offer full > off-grid support. While I’m fully aware of the drawbacks of their system > architecture for off-grid setups, it’s also important to acknowledge that no > manufacturer is “too big to fail”—but Enphase is about as close as we have > right now. If something were to happen to them, the reliance on remote access > for the system functioning is concerning. It could essentially become a big > brick if a service issue arises and there’s no support. On the other hand, > Enphase may be a safe bet for certain off-grid systems if you think they will > come out on top. > > But the reason I bring Enphase up is modularity. Building systems with > interconnected components from various brands can spread the risk. Sol-Ark, > with its “battery agnostic” approach, is a reasonable choice, as long as > there’s a replacement all-in-one option if they were to go out of business. > EG4 and Midnite seem to offer alternatives in that space now. As long as > LiFePO manufacturers stick with 48V/51.2V standards, complete battery > replacements should be straightforward. However, I do think that large > battery sizes like 5 kWh (or even 13.5 and 14.3 kWh) could be problematic. > Personally, I prefer the concept of smaller, 1 kWh chunks. In the case of a > 40 kWh battery bank, for example, if one module fails and the manufacturer is > no longer around, it’s a lot easier to deal with. That's similar to how we > can drop one faulty 2V cell in a series of 24 lead acid batteries sometimes. > Enphase, if you think about it, is the least modular approach in some ways, > since it relies on a single manufacturer with a proprietary system. So the > whole concept of modularity is not straightforward, either. It's a fantasy at > this point to hope for a truly modular and manufacturer-agnostic system. > > What I find interesting is that most of my clients who went off-grid 7-15 > years ago are pretty understanding when I tell them it’s time to replace > their systems. Realistically, fast-forward another decade, and we’ll probably > see significant advances that make a complete system replacement worth it > once again. I’m not saying we should be designing disposable systems, but > that might be where we’re headed, just like so many other industries. Think > of what Tesla is doing with the Powewall 3. They are making solar and > batteries as cheap as possible (while maintaining high quality standards and > keeping fuel in Elon's jet). However, when the PW4 comes out, the PW3 will be > deprecated, and those systems will become essentially disposable. The > warranty is only 10 years. So when the inverter insude the PW3 dies in year > 11, guess what – the entire PW3, battery and all, may be rendered useless. > But, people still flock to Tesla for backup systems. And for good reasons. > > The days of keeping systems running on old components while upgrading just > parts of the system are probably behind us. The rapid evolution of > technology, equipment, codes, safety, and consumer needs will make whatever > we install today obsolete soon after it's up and running. > > > > --end rant-- > > > Jason Szumlanski > Principal Solar Designer | Florida Solar Design Group > NABCEP Certified Solar Professional (PVIP) > Florida State Certified Solar Contractor CVC56956 > Florida Certified Electrical Contractor EC13013208 > > > On Tue, Sep 17, 2024 at 5:20 PM Ray Walters via RE-wrenches > <re-wrenches@lists.re-wrenches.org > <mailto:re-wrenches@lists.re-wrenches.org>> wrote: > Honestly, that advice would seem to be true, but the reality is: It is > not valid. Just look at Blue Planet, that was supposed to be a top tier > offering. Solar World? AEE? Magnum has had serious issues, Outback > doesn't answer the phone, SImpliphi takes an attorney to honor their > warranty. Even long standing companies are not sure bets, at all. They > do cost much more, so I'm not sure who to turn to anymore. I'm about to > install Rubix LiPO4, which comes in a 24 v offering, BTW for Dave. > > The biggest issue I've seen with old VFX inverters, is the LVD set point > can't go high enough for LiPO4. I use the aux out on a charge > controller, to switch on and off the remote switch on the VFX. > > I like the Fortress with Solark combo, but its not without its troubles > either. If the Solark shuts off due to low voltage, so does your PV > input. Then the no load draw on the Fortress eventually shuts down the > battery. You really need some (at least 1 kW) of DC coupled PV to keep > that death spiral from happening. > > Ray Walters > Remote Solar > > On 9/17/2024 12:23 PM, Sindelar Solar via RE-wrenches wrote: > > Jerry, > > Re your advice to never get startups or small manufacturers as so many > > disappear and now you are stuck, I guess we should stick with the big > > well-established manufacturers, like Outback, Magnum and Blue Planet, > > right? > > As you would say, fun times... > > Allan > > > > On 9/17/2024 10:58 AM, Jerry Shafer via RE-wrenches wrote: > >> Dave, > >> I would suggest stepping up to 48 nominal, fortress 18.5, battery 12 > >> or 15 k solark inverter, re-wire the array to single or dual string, > >> make the wiring in the home capable of 240, this usually requires > >> main panel re-work and set up the monitoring. > >> Batteries are like replacement heart valves, never get startups or > >> small manufacturers as so many disappear and now you are stuck. > >> Fun times. > > > > _______________________________________________ > > List sponsored by Redwood Alliance > > > > Pay optional member dues here: http://re-wrenches.org > > <http://re-wrenches.org/> > > > > List Address: RE-wrenches@lists.re-wrenches.org > > <mailto:RE-wrenches@lists.re-wrenches.org> > > > > Change listserver email address & settings: > > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > <http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org> > > > > There are two list archives for searching. When one doesn't work, try > > the other: > > https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ > > <https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/> > > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > > <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org> > > > > List rules & etiquette: > > http://www.re-wrenches.org/etiquette.htm > > <http://www.re-wrenches.org/etiquette.htm> > > > > Check out or update participant bios: > > http://www.members.re-wrenches.org <http://www.members.re-wrenches.org/> > > > _______________________________________________ > List sponsored by Redwood Alliance > > Pay optional member dues here: http://re-wrenches.org > <http://re-wrenches.org/> > > List Address: RE-wrenches@lists.re-wrenches.org > <mailto:RE-wrenches@lists.re-wrenches.org> > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > <http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org> > > There are two list archives for searching. When one doesn't work, try the > other: > https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ > <https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/> > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org> > > List rules & etiquette: > http://www.re-wrenches.org/etiquette.htm > <http://www.re-wrenches.org/etiquette.htm> > > Check out or update participant bios: > http://www.members.re-wrenches.org <http://www.members.re-wrenches.org/> > > _______________________________________________ > List sponsored by Redwood Alliance > > Pay optional member dues here: http://re-wrenches.org > <http://re-wrenches.org/> > > List Address: RE-wrenches@lists.re-wrenches.org > <mailto:RE-wrenches@lists.re-wrenches.org> > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > <http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org> > > There are two list archives for searching. When one doesn't work, try the > other: > https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/ > <https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/> > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org> > > List rules & etiquette: > http://www.re-wrenches.org/etiquette.htm > <http://www.re-wrenches.org/etiquette.htm> > > Check out or update participant bios: > http://www.members.re-wrenches.org <http://www.members.re-wrenches.org/> > > > > -- > > > > Mac Lewis > > "Yo solo sé que no sé nada." -Sócrates > > _______________________________________________ > List sponsored by Redwood Alliance > > Pay optional member dues here: http://re-wrenches.org > > List Address: RE-wrenches@lists.re-wrenches.org > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > There are two list archives for searching. 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