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Todd Wackford avatar image
Todd Wackford asked

Need help understanding SOC - Incorrect Setup?

I'm not sure I have my BMV-712 setup right. I have 4 Battleborn 100ah batteries in parallel for a 12 vdc system and a Tristar MMPT 60. If you notice in the graphs, the SOC slowly drains overnight to around 70% which is what I expect with the things are are running. In the morning when the solar starts generating power, the SOC jumps to 100% over a very short time. Is that correct? Also, the MPPT still is inputting quite a few amps into the batteries which doesn't make sense if they are at 100% SOC.

I think I need some education.
TIA

SOC
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2 Answers
Murray van Graan avatar image
Murray van Graan answered ·

The BMV needs to be programmed according to the battery manufacturer’s data sheet. It needs to know the battery capacity, charged voltage, tail current and peukert exponent amongst other settings before it will accurately display SOC. In your case, the SOC jumps quickly as the BMV thinks the battery is full, where it might be not. See the manual


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Todd Wackford answered ·

Somehow my "Charged Voltage" was set down to 13.2V. I think maybe that when I created the "VE.Smart Networking" and then subsequently removed it, it changed the Charged Voltage from 14.4V to 13.2V. I may mess with it later to see if there is a bug. First I'll let it run correct for a day or two.

Thanks for the response.

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