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ranjer asked

BMV-712 incorrect battery voltage

I recently installed a BMV-712 on a 24v system (four 6v wired in series) with a 224AH capacity. For some reason, the display (on both the unit and on my phone using the app) shows only 7.1v which seems to be for only one battery of the series. I connected the wire for the BMV (the temp sensor and power wire) to the + terminal on the last battery in the series. Could this be the issue? The rest of the monitor seems to be working fine? This discrepancy appears both in the settings and the display of battery voltage.

BMV Battery Monitor
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2 Answers
Mark avatar image
Mark answered ·

The probe must be connected to the POSITIVE of the FIRST battery in series.

The shunt must be connected to the NEGATIVE of the LAST battery in series.

Fix this up & it will work fine! :-)

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ranjer answered ·

That worked. Had to rearrange to get power cable to reach shunt (why I had done it the other way to begin with). I didn't realize the powerline to the shunt was also what detected the battery voltage. Thanks much.

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