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MPPT and BMV712 settings

Please give me feedback on the settings below, do they look ok?

We have Six 6 volt Lead Acid Batteries paired in series totaling 840Ah with the following specs:

*Bulk Charge: Constant current @~10% of C/20 Ah in amps to 2.45+/-0.05 volts per cell (e.g. 7.35 volts +/-0.15 volts per 6 volt battery)

*Absorption Charge: Constant current @~10% of C/20 Ah in amps to 2.45+/-0.05 volts per cell (e.g. 7.35 volts +/-0.15 volts per 6 volt battery) Constant voltage (2.45+/-0.05 vpc) to 3% of C/20 Ah in amps then hold for 2-3 hours and terminate charge Charge termination can be by maximum time (2-4 hr) or dV/dt (4 mv/cell per hour)

*Float Charge (Optional) Constant voltage 2.17 vpc (6.51 volts per 6 volt battery) for unlimited time

*Battery temperature adjustment: reduce the voltage by 0.028 Volts per cell for every 10°F above 80°F, increase by the same amount for temperatures below 80°F.

We have 3 separate 100/30 smart MPPT charge controllers for 3 solar panels, and a BMV 712.

•Current setting on MPPTs:

Absorption: 14.7V max 6 hrs

Float: 13.2V unlimited

Temp. Adjustment: -16.20mV/C

Load output: battery life

Tx port: normal communication

•BMV settings:

Battery capacity: 840Ah

Charged Voltage: 14.3V

Tail current: 4%

Peukert exp: 1.25%

Charge eff: 95%

Current threshold: 0.10mA

Synchronization: on

Do these setting optimize our system? Any feedback is appreciated

Thanks, Caren


MPPT - Solar Charge ControllerBMV Battery MonitorBMSlead-acid
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1 Answer
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bigbillsd answered ·

Assuming your 6 batteries are serial/parallel connected for 12v then each battery is rated for 280 AH at 20 hours? Is that correct? In regards to the voltages, your battery manufacturer specs for those exact batteries should be used.


-Bill

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