question

Duncan avatar image
Duncan asked

BMV 702 Battery capacity dropping

Hi

My batteries are going into FLOAT every day but the dsplayed battery capacity % is gradually reducing over a few weeks (ie, the batteries are not degrading).

What is the likely cause?

Should I have to reset 100% SOC frequently?

Is my shunt installed correctly with respect to the 12v fuse block? The shunt is out of picture but is in the negative cable leading out of the bottom of the picture.


thanks



BMV Battery Monitor
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2 Answers
Justin Cook avatar image
Justin Cook answered ·

Hi @Dunk O, I'd have to actually see the shunt to tell whether or not it's installed correctly; if you're seeing the SOC constantly going down, it's a good sign that your charge source is bypassing the shunt (ie, connected directly to the battery, which it must not be) or that perhaps the shunt is wired incorrectly in some other way. Please post some photos both of the shunt itself as well as the battery bank (so that we can see what's connected to them both) and we can help troubleshoot from there.

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Duncan avatar image
Duncan answered ·

I fogot to say the that the gradual drop in indicated capacity was down to 95% over a couple of weeks. BMV did reset capacity to 100% itself yesterday. Maybe I am seeing normal BMV behavior?


Picture of shunt uploaded. There is only one negative cable leading to the battery and that comes from the bootom of the shunt. All load negative cables enter the top of the shunt (some via the terminal block)

Thanks for checking - much appreciated


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