question

happy-days avatar image
happy-days asked

Random voltage spike | Incorrect Temperature Reading

Hi there,

We have recently experienced random high voltage alarms of 14.7v – 14.8v (12v system) when charging our battery bank via solar.

We have a BMV-712 with factory settings applied, along with Victron MPPT’s, charging a gel battery bank (800ah).

We believe the cause of the issue is a bad/incorrect battery temperature reading. Where battery temperature randomly pops up at -1c (first attachment); and the system allows additional charging voltage in lieu of an incorrect lower temperature, which spikes the voltage and sets off the alarm.

This is despite the AUX input on the BMV being ‘None’ (second attachment).

Normally, the MPPT’s show no temperature as per third attachment. So there seems to be a direct correlation with the temperature reading appearing at -1c and the voltage spike.

Noting, we are currently very close to the equator so temperatures are on the warmer side.

The fix at the moment has been to reset the BMV to defaults; however it has done it a number of times now, sometimes weeks apart.

We plan to leave the vessel for a number of days and need to ensure batteries are not going to over charge.

Hoping there is a fix that you can help with.

Looking forward to you wisdom and guidance.

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MPPT ControllersBMV Battery Monitor
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img-1638.jpg (144.3 KiB)
img-1640.jpg (164.3 KiB)
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1 Answer
kevgermany avatar image
kevgermany answered ·

Might be a Bluetooth update missing, see posts from @mkuiken in this thread


https://community.victronenergy.com/questions/235215/mppt-controller-suddenly-not-working.html

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