Life solar battery regulator / BMS conflict

[surfpac44]

Hello
I am Sylvain, I am 44 years old, I have lived in the depths of Morocco for 20 years and my house has always been 100% autonomous.
I have a solar panel park and a wind turbine.

Here is my system.

2 LiFePo4 batteries of 5,2kWh each.
1 outback flexmax FM60 regulator.
1 Victron 2000VA inverter.
1300 w of solar panels.

I recently swapped my fleet of 4 gel batteries for 2 Litium iron phosphate batteries with the BMS.
I haven't changed my charge controller, which is still the outback flexmax 60. According to the outback company, my model is compatible with lifePo4 technology. Here are the settings I made:

28,6 V absorption
Float 28,4V
Current limit 60 A
Bundle 28,1V
Absorption time 0,0 hours
absorb final amps 00 A

I find myself with a problem: as soon as the batteries are at 100%, my elec stops (it recovers, then stops again and so on, I have to cut the solar charge to be quiet, the time that the batteries lose some of their charge) I can't find the appropriate setting on the flexmax. Do you have a solution? (the inconveniences: fire alarm which goes off at each cut as well as the protection box of the water pump which jumps and which I have to restart each time. My house is no longer autonomous...)
Thank you very much for looking into my case.

Silvan

[Christophe]

Before talking about the problem: is there a problem with the PV power?

10.4 kWh of battery for 1300W of PV does it seem a bit tight? Even in Morocco? No ?

For your concern: do you have access to the BMS settings?

There cold, I assume a safety BMS on the output MosFET overvoltage?

Do the controller and BMS communicate with each other?

[surfpac44]

Hello,
Thank you very much for your answer.

No, at noon, the new LiFePo4 batteries are full and my 4 old Victrons gel of 220Ah, it was a little longer but in the afternoon, it was full. I almost increased for cloudy days, but they are so rare where I am that I left it like that. They are 20 years old.

No, I do not have access to the BMS, these are batteries sold on the net on a site selling solar equipment and the guy told me that they were NEC batteries from the automobile, reconditioned for use household in a stainless steel case. I don't have the load parameters so. Does all LiFePo4 technology have the same setting....?

The BMS and the regulator are only linked by the fact that my 2 24V batteries are directly connected to the regulator. No other cables.

thanks.

[Forhorse]

Seen from a distance like that I would also say that it is the BMS which cuts in overvoltage protection.
You should try to modify the charge parameters of your solar regulator (the best would be to have the characteristics of the batteries and to adjust the regulator accordingly)
Start by setting the absorption and float parameters to 27V to see what happens, then what the BMS says about the SOC once this voltage is reached.

[surfpac44]

Thanks, I'll try that tomorrow.

[surfpac44]

I set floating and absorption to 27V. I was previously advised to avoid the absorption phase if possible for lifePo4 so in advanced menu, absorb time is set to 0,0h and absorb end Amps is 00A.
and for the result of the setting at 27V
At 100% load this afternoon, cut again. I do not have access to the BMS menu, it is internal.
I asked the seller for the characteristics of the BMS, no answer...
there you go....

[izentrop]

2 LiFePo4 batteries of 5,2kWh each.
1 outback flexmax FM60 regulator.
1 Victron 2000VA inverter.
1300 w of solar panels.

I recently swapped my fleet of 4 gel batteries for 2 Litium iron phosphate batteries with the BMS.
I haven't changed my charge controller, which is still the outback flexmax 60. According to the outback company, my model is compatible with lifePo4 technology. Here are the settings I made:

28,6 V absorption
Float 28,4V
Current limit 60 A
Bundle 28,1V
Absorption time 0,0 hours
absorb final amps 00 A

I find myself with a problem: as soon as the batteries are at 100%, my elec stops (it recovers, then stops again and so on, I have to cut the solar charge to be quiet, the time that the batteries lose some of their charge) I can't find the appropriate setting on the flexmax. Do you have a solution? (the inconveniences: fire alarm which goes off at each cut as well as the protection box of the water pump which jumps and which I have to restart each time. My house is no longer autonomous...)
Thank you very much for looking into my case.

Silvan

Hello, I don't know anything about it but

For a 24 volt system, we recommend checking the settings. For volume and absorption it should have an output of 28,8 volts and for float it should be 27,2. Please disable your equalization if possible, and if not, set it to 28,8 volts.

https://battlebornbatteries.com/set-out ... n-battery/

Have you turned off EQ? which is done with PB batteries but not for lifepo4?
Voltage floats wouldn't help either.
Why this limitation of the absorption time? The lifepo4 can charge at 1 C. https://www.power-sonic.com/blog/how-to ... batteries/
https://www.outbackpower.com/downloads/ ... french.pdf

[surfpac44]

Goods.
Yes equalization is disabled.
In fact, I'm lost on the settings.
I'm told a bit of everything and suddenly, I grope.
Nothing specific.