Hi guys ,
I am trying to find a way to stop my mppts to charge the batteries at soc 80 or 90%
No mater how i lower the Absorption or Float still it charges them in float to 100%,
is there a way to do this exactly?
How do you measure your soc ?
With the victron smart shunt,
I have shunt and cerbo gx
It’s to difficult to set Soc by voltage alone for LiFePo4 batteries.
The charge/discharge voltage curve is to flat to be a useful guide.
And the only time that the battery cells get effectively balanced, is when the cells are being held at the absorption voltage.
You could use a BMV, use it’s relay to switch the mppt charge off via a Ve Direct non inverting cable.
Of course, BMV’s are not 100% accurate.
After a couple of weeks of not fully charging and balancing the battery, there will be some difference between the battery Soc, and BMV displayed Soc.
And a poorly set up BMV is not accurate at all.
Just discovered i can adjust maximum voltage the chargers put out from the DVCC, if i set max voltage charge to about 28v that should do it ,
What do you think ?
You could have an 8 cell LiFePo4 fully charge at 27v.
Very s l o w l y of course.
And cell balancing might not occur.
Lowering the battery voltage will increase the time taken to charge the battery.
Not a good thing if charging from solar.
Or after a grid failure/rolling blackouts.
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Lowering dvcc (battery charging voltage) is not doing anything 
, it s charging way over 27volts
