question

ajsmuts avatar image

BMV 700 Monitor not updating battery capacity from solar

System MPPT 250/60 with 6x 330W solar panels and 2x4x12V batteries = 48V.

Everything works fine except BMV monitor battery charge reading that starts with 100% after reset but then keeps on dropping to 0% notwithstanding full charge daily usually to float state. All other readings, e.g. incoming solar current, voltage and power seem to be accurate. All settings checked and verified electronically + internet by certified installer and also by an independent certified electrician.

During rain or clouds with partial charging the battery status is my guess only. When then charging overnight from external Lister generator the battery level is accurately updated all the way to float and 100%, so the monitor does work for external charging.

What must be changed so that the monitor updates the battery charge from incoming solar power and can tell how much capacity is still available?


BMV Battery Monitorbattery capacity
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1 Answer
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

I guess the negative of the MPPT is connected directly to the battery instead of the shunt; all system negatives must be connected to the "loads" side of the shunt so that the monitor can measure current into and out of the batteries.

Please review the user manual and quick connect guide and correct the installation as necessary.

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