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Details? Well, this is what I used for battery: https://batteryhookup.com/products/new-12v-100ah-lifepo4-kit-w-bms-low-temp Overkill to be sure, but it included the BMS, and I didn't need to mess with bus bars as the cell packs have flexible wires. The four cell packs fit very nicely into the...

Sed linked to an ASI breaker on homedepot.com, but they sell directly, and have DC breakers rated at 125vdc/pole. Using a two-pole breaker on positive and negative, according to the datasheet, would give up to 250vdc. Here's an example, a two-pole 50A breaker at 250vdc...

Maybe the manual has been updated, or maybe I overlooked this previously, but the answer seems to be here:

I ended up buying both a USB-RS485 and a USB-UART adapter off eBay. The 485 still didn't work, so that's three separate RS485 adapters that didn't work--I'm not sure if my BMS is just defective or what. Fortunately, I am able to communicate using the UART adapter. I'm using this software to...

My order arrived yesterday, appears to be just as described (except that the screws aren't security T8 as the page says; they're perfectly normal T10 instead). Though I'm starting to wonder if I haven't bitten off more than I can chew--getting these into a 12P8S configuration is going to take...

I placed an order on Thursday, got a shipping notification yesterday, and FedEx confirms they have the package. Maybe I got lucky.

Maybe I've missed it in this thread, but I haven't seen any discussion of the communication protocol--is that documented somewhere I haven't seen?

Yeah, I should have updated the thread. I adapted one of Will's milk crate builds, leaving out the solar charge controller, and using 4x 100Ah packs from batteryhookup.com. Way overkill for the power capacity, but it's working well so far.

I'm open to building or buying. I'm willing to pay a bit of a premium to buy--it'll look much more "finished", which will help the WAF (and this will be in her domain), but that depends on there being a commercially-available product that does the job and isn't multiples more expensive than...

So I ended up not using SolPipLog; it doesn't support the protocol of my inverter, and it will only run on a Raspberry Pi (despite supposedly being open-source software, the developer doesn't release the source code). Instead, I'm using mpp-solar: https://github.com/jblance/mpp-solar It does...

Perhaps my question wasn't clear. I understand that there are three different wire protocols; I'm wondering about the data protocols. CAN may be its own thing, but UART/RS485 are serial communication protocols. So I plug in a USB/serial converter, I set it up with 9600/8n1, and I can talk to...

If not, I'm sure it could be reverse-engineered readily enough--but it'd be much nicer to have the standard, so we'd know how it should work.

Fair enough. A little further digging around suggests that in my application, I'd want a "common port" BMS, and the configuration of this pack suggests it's using a "separate port" one. Starting to sound like it could be a problem, as there isn't going to be any way to make the UPS charge...

...not accounting for charging. At 60A (the maximum) of utility charge, that would add another 12-14 amps, assuming a perfectly-efficient charger. You're right that I'm not intending to run it at full load continuously, but it doesn't seem like a good plan to cripple the thing unnecessarily...

From what I could see in the video, it was only securing the top of one given piece--so that, for example, the top of piece 1 can't spread open. It doesn't appear to do anything to connect piece 1 to piece 2 that I could see.

Interestingly, my big UPS is an APC 3000 XLM. I don't have that software, but I didn't see anywhere in the video where he adjusted any voltages--the only adjustment I saw was to turn off the beeper. But good to see I'm not the only one thinking this way.

I'm not sure there's a "cutoff" as such; as far as I can tell, both units apply a float charge. On the APC, the web interface reports a "battery voltage" of 54.81 volts with fully-charged batteries; I'm assuming (1) that's an accurate value (I haven't yet probed it with a DMM), and (2) the...

For background, see this thread: https://diysolarforum.com/threads/lifepo4-for-ups-battery-replacement.6127/ tl;dr: I'm wanting to assemble a 24v LiFePO4 battery pack of around 20 Ah capacity to replace SLA batteries in a UPS. I realize this is quite a bit lower capacity than most folks around...

Since it's pretty well all up and running now, here's what I have set up in my workshop. I'm using eight 250W panels from SanTan Solar, a MPP Solar LV2424, and 8x 272Ah LiFePO4 cells for storage, to run my server rack, and hopefully bring the electric bill for my workshop lower than the one for...

So just to make sure I'm not missing anything--"double-conversion UPS" is really just line -> charger -> battery -> inverter -> load, right? Ignoring trying to get fancy with monitoring, of course.

...which it is for me. But the BMS would handle this on a per-cell level, right? Though the question remains how the UPS would deal with its battery apparently dropping offline.

Well, I pulled the trigger on the smaller one--rather than go right for the 48V unit, I bought this 24V, 20Ah pack for the smaller 1500VA UPS: https://www.aliexpress.com/item/4000365119448.html?spm=a2g0s.9042311.0.0.431d4c4dLimdTC This will mean some minor surgery to extend the UPS's battery...

I'm waiting on a couple of parts to be able to effectively monitor voltage (and current) over time, to get a better idea of what the UPS is doing when charging its batteries. But while I'm waiting on those, any suggestions for cells in the 20Ah range? Most of the discussion I see here is for...

I'm considering building a system around a LV2424 inverter for use in my shop. As I read the manual, I see it calls for overcurrent protection on the grid input. However, I don't see anywhere in the manual a specification for max AC input current. Is it just a matter of making sure it doesn't...

I suspect neither of those are needed. The USB adapter shouldn't need external power; it gets it from the USB port. And, as you say, the BMS itself has power. AFAIK, RS-485 signaling just takes the two wires. Won't be able to test it for sure until my cells arrive (a month or more to go on...

The mounting hardware is Rib Brackets from S-5, which I found at altestore.com. Surprisingly expensive, really--even without rails and racks, I still spent half as much on that hardware as I did on the panels. The server rack ordinarily draws 1-1.2kW, so the batteries power it for 5-6...

But they're both fed by the grid, when the unit is running on grid (which mine would be a good part of the time). Hidden indeed--thanks for the spot, I'd missed that. Seems like that's something that should have been mentioned on page 6, where it says you're supposed to use a breaker on the...

Wondering if someone can give me a hand with my 485-to-USB device from the unit I bought back in May. Rather than a single cable, I have two. The first, apparently, is a USB-to-485 cable, whose end looks like this: The screw terminal block unplugs from the other part of the green connector...

It's too high for "US wiring" if you were planning to just plug it in to a wall outlet for its grid input--I don't think that's really what this system's designed to do. And yes, it has 60 amps charger output, but that's output to the battery, at battery voltage. If I use Will's recommend...

https://www.asi-ez.com/member/~NDB2-63C40-1.asp? Oh, need two of them for two inverters? https://www.asi-ez.com/member/~NDB2-63C40-2.asp?