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colindernst avatar image
colindernst asked

Why does state of charge drop while voltage is high?

I have 200Ah of lithium batteries monitored by a BMV712. From fully charged batteries the only draw on the system is a fridge (I have turned everything else off) which draws about 3Ah. Overnight the SOC has dropped to 17% with a voltage of 13.3v. This situation happens consistently when I have been using the system in the past. I have reviewed my settings but perhaps I am still missing something there. Do you know of a reason why the SOC drops so quickly with very little load on the system?

BMV Battery MonitorSOC
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3 Answers
wkirby avatar image
wkirby answered ·

What value do you have in the "Battery capacity" field within the Battery settings page?

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colindernst avatar image
colindernst answered ·

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klim8skeptic avatar image klim8skeptic ♦ commented ·

What are your shunt settings?

shunt-1.png


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wkirby avatar image wkirby ♦♦ commented ·

The next thing I can think of is the current reading. What does the actual current when just the fridge is on? Naturally, it should read quite low or ideally 0A when there is no load in the system at all. If the calibration is off then it might think that more current is flowing that what actually is.

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A zero current calibration can be performed to ensure that it knows what 0A is, but you need to be sure that 0A is indeed flowing through the shunt when you do this.

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askdba avatar image
askdba answered ·

I have the similar problem, do we have any updates on this?

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Related Resources

Victron BMV battery monitors product page

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