question

gumalu avatar image

Victron AC coupled micro grid with Fronius and BYD ESS configuration question.

I have AC coupled micro grid istallation with 2 quatro 2 Fronius Primo and a BYD B-Box 10.5


When i configure the battery with VE configure in the charger tab like this

Battery type : Lithium

Absorbtion voltage 56.8

Float voltage 54

and ESS like this

The system is running fine the 2 quatros go in to Float but the battery is only at 99% 54.2V

because in the configuration Flost voltage set to 54V.


When i change the configuration in the charge tab to the values suggested in the

Victron & BYD B-Box manual

Absorption voltage 55.2

Float voltage 55

under battery type is says : no corresponding default

and in ESS i get this message

When i keep the settings as in the Victron & BYD B-Box manual

Absorbtion voltage 55.2

Float voltage 55

The system is running but it never gets in to Float sate is switching between Bulk and Absorption

charging the batter to 56.4 volts and then discharging to 54V and so on.


So what are the correct setting here for the BYD battery?

BYDvictron products
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ESS is setup up as : keep batteries charged

1 Answer
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boekel answered ·

Basically the batteries BMS will take over the voltage settings when the system is configured correctly, the settings in the Quattro's you can see as a safe backup setting.

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Not really. There is no fail safe battery charger settings because any loss in CAN comm will render the Multi in passthrough mode