This topic covers the reported SOC being out of sync with the actual battery voltage or state. It covers BMV battery monitors, SmartShunts, Lynx BMSs and Lynx Shunts and will just be called shunt below. It is also assumed that the shunt is monitoring the domestic / house / cabin battery bank and not…

Oh my…a nicely detailed and understandable explanation even for woman UFO, like me.:grinning::wink:🫶🏻 Happy to see it that I am not alone with the similar problem😁

Hi and thanks id been googling for to long lol Now system apears to be working properly :pray:

This all makes good sense, thanks! I have a question: I have a 280Ah LFP battery, so a 4% tail current is in the 11A range. However, my solar is comprised of a single 100W panel, so I never see more than ~6A from the MPPT, even in full sun. As such, what should I be setting that tail current to? T…

Hi i’m Alex from the Netherlands. i have the same problem also an Reset problem with the Smart shunt. I’ve been using a Livepo4 battery system 24v for two weeks now and have installed a smart shunt. 500A/50 mV. The problem is a regular reset to 100% SOC. I’ve copied Lifepo4 various settings from…

As has been said elsewhere post a screenshot of your SmartShunt settings and of your MPPT settings. We can not help without data.

I don’t understand this website. How do I post an image? I’ll retype everything.

Battery capacity 360 Charge voltage 26,4 Current Measurement direction Normal Discharge floor …

If you read through the FAQ you will see that the 26.4V for the Charged Voltage is too low and is causing your SmartShunt to reset to 100% too early. This should be set 0.2V below absorption, so if you have an absorption voltage on your MPPT of 28.4V then set the SmartShunt Charged Voltage to 28.2V…

[image] Lex63: How do I post an image? I’ll retype everything. Use the upload button [Screenshot_20251201_132645_Chrome]

Battery monitor jumping to 100% or reporting a high SOC with low Volts / the BMS shuts down

DIY

pwfarnell 14 June 2025 09:25 14

For a discussion of this edge case see the detailed question and answer here.

Tail current setting with low charging power

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Battery monitor jumping to 100% or reporting a high SOC with low Volts / the BMS shuts down

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