SOC comes from the battery. I don’t know if you have multiple batteries does the AIO go with the lowest SOC or average? I digress. Everyone who’s used a trimetric or similar has seen this. The % meter gets off in its measurement of SOC and it gets worse the longer it goes before the battery gets full to reset the SOC. Lithium are exactly the same. The Bms/SOC is only as good as how often it’s recalibrated by getting full. And it’s why some lithium/nverter OEMS for off grid say going with volts is more accurate than %. What happened in this case was the SOC/BMS got off in its calibration and the inverter is not smart enough to be able to use the 2 forms of metering ( volts/soc) to figure its actual SOC and so the battery shut down because it got to its LVD voltage. It’s another glaring issue/problem with using just SOC. As SOC is subject to the exact issues we’ve seen for 30 yrs and when the old lead battereis got old and weird or many days or more between getting full, what did we tell clients, use volts because the SOC isn’t working properly anymore. The inverter should be smart enough to be able to use both volts and SOC. Most battery companies tell me batteries should be charged to 100% weekly. It’s not for the cells it’s for SOC accuracy. Jay On Jul 15, 2025, at 7:23 PM, Kirk Herander via RE-wrenches <re-wrenches@lists.re-wrenches.org> wrote:
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