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garretts70a9 avatar image
garretts70a9 asked

BMV-712 State of Charge vs Consumed Ah

Hi All,

I have a BMV-712 monitoring 2x200Ah Lithium batteries. It seems to me that the State of Charge does not correspond to the Ah consumed. For example:

img-2103.pngimg-2104.pngFrom my perspective, I would expect that the state of charge should read around 47% and yet it reads 72%. Can anyone why this may be or a potential fix for this?

Thanks in advance.

BMV Battery Monitor
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JohnC avatar image
JohnC answered ·

@garretts70a9

That's caused by the Peukert setting, which is crediting your SOC for low dicharge rates. That default 1.25 is for Pb batteries, and even then is on the high side. For Li batts Victron recommend starting at 1.05 and Charge Efficiency at 99%.

The Ah vs SOC relationship will be much closer, but won't be perfect unless you set it to 1.0 Peukert.

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garretts70a9 avatar image garretts70a9 commented ·
Thanks for that. You got me pointed in the right direction and I learnt a lot about that stuff now. Changed to your recommended settings and now it looks good.
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