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gcrank1
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# Posted: 21 Nov 2025 11:32am - Edited by: gcrank1
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An LVD at 11.7 isn't really low as the BMS is a safety trip, not supposed to be a regular 'run until it drops off' kinda thing (they do wear out I hear). That low it gives the bat the ability to have its voltage drop under load in the lower knee of voltage and not switch off early yet save the bat from dropping too low into the danger zone.
I know the LVD on the inverter is even lower so mine hasn't been shutting down since getting the LFP's; it did when I ran the old LA bats down too low (guess that effectively tested the inverter safety switch too).
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paulz
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# Posted: 11 Feb 2026 09:54am
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Let’s see, where were we.. I’m still using the old Valence bank, new ones sitting. 95% generator charging, small bit of solar. One Meanwell charger.
Lately even after an hour or two on the charger the bank would show 13.6, quickly down to 13.2 once charger off, 13.0-1 by morning, lasting all day until evening charge.
Yesterday I checked the meanwell unhooked from the bank. 14.1 where last set. I cranked it up to 14.6, hooked back up and the bank rose to 14.6 quickly., down to 13.8 shut off, down to usual 13.2 and 13.0 this morning.
So, as Steve has told us, the extra charge voltage really doesn’t help much. I forgot to mention the charge amperage is about the 40 amps the meanwell puts out, either way.
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gcrank1
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# Posted: 11 Feb 2026 11:36am
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That is pretty much my experience too, the settled/resting voltage is where we start drawing power from so I guess if we want more time to run or bigger loads what we need is more battery bank (now that Is the Same as with LA).
We have a Feb thaw now so for V-Day we are going to cabin (happy dance!), my LFP there should be ready to run the fan(s) to mix the heating air, at least it was when we were last there (it have no charging going on). I also have the little portable LFP (Ecoflow?) and the inv/gen there. My notes on that cabin bat are there; ie, how many hrs at what load I was getting so I could track its real-world capacity.
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Steve_S
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# Posted: 11 Feb 2026 01:27pm
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@Paulz, I just wanted to add a wee detail here. I have both a Meanwell setup that can push 50A at a 24V Battery Pack but I also have a proper Lab grade charger for cells that can push 40A @ 3.650V per cell. I upgraded the charging wires after some hair pulling to 6-AWG Ultra-Fine stranded pure copper in silicone jackets which pretty much eliminated all line loss & resistance. Wire from Charger to Pack/Cell can be such a royal PITA and even coarse stranded wire is of little help...
My oldest LFP cells are "Bulk Grade" and 7+ years old now (gee time flies) and they've worked but never strained at any time. I can charge these up to 3.450V per cell / 27.600V and let them settle to a point where they take no more than 1A and shutoff. They will within 20 minutes (without load) settle to 26.9 and once I add even a tiny load they will hit 26.7V or 3.3375V per cell with a slight imbalance usually below 0.010V between cells.
Now these are earlier LFP and "BULK" grade meaning they did not qualify as B Grade & certainly not A-Grade.
ON THE FLIP !
I have 3 Packs of A-Grade Matched & Batched cells and I can charge those teh same way but they settle at a much higher voltage (3.395 /3.400) without load and will only drop another 0.010 with a light load which is right on target and that is also at 15C/59F temp. * Remember, I keep my powerhouse/pumphouse heated to 15C in winter. In the summer they settle (lose) less because temps are closer to the optimal of 25C/77F.
NOTE: The 6-AWG wire I use had to be imported from one of my industrial suppliers in China as I could not find anything close at domestic suppliers & I searched hi/lo. The "Utra-Fine" pure red copper wire is essentially "Angel Hair" thin and if my recollection is correct, there is something like 600 strands in that wire... I mean it is REALLY thin ! Interestingly, the wire is rated for 800VDC ! It is not stuff you will find easily.
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paulz
Member
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# Posted: 11 Feb 2026 05:52pm - Edited by: paulz
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Thanks Steve. Wondered about wire gauge too, since I rewired for the Victron SCC. I have 4 awg from meanwell to splitter, 8 awg to each battery.
Bank holding pretty well today. Wife has been watching Walker Texas Ranger all day on the 40” big screen while I make firewood, bank still at 13.15 at 3pm. Maybe yesterday’s 14.6 charge jolt woke them up a bit.
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