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launacorp avatar image
launacorp asked

MPPT 100/20 Batterylife inital cut off voltage

Hi erveryone,


is there an option (if not could it be implemented) to set the inital cut of voltage of the batterylife algorithm?


Background:

I have an offgrid system with 4x100W south an 4x100w east and 280Ah 24V lead acid.


I read a short time ago, that the inital cut off voltage is 11.8V with increasement of 0.2V. Because I know the overall capacity per day (around 24.3V in the morning with float Charge until ~18:00 the the last day) I would like to set the inital voltage to 24.2V on the batterylife algorythm. 11.8V is way to low for my opinion.


Sure I could let it run for some days, but why discharge the Battery so much if it should't be.


We all know that the maximal charging cycles on lead depends on the maximal discharge on the battery amongst other things.


So do you see a posibility that VICTRON could implement this in there Firmware? Certainly this couldn't be more than 10lines of Code.

MPPT ControllersBattery Protect
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2 Answers
JohnC avatar image
JohnC answered ·

Hi @launacorp

You mean the settings for the Load output?

You'll find this option already exists in VictronConnect, with multiple algorithms to select from, and the option to set your own.

Your '11.8V' default will be for a 12V system, and double that for 24V.

Unless I'm offbeam, what you want already exists, and there'll be more than 10 lines of code involved. Check it out..

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launacorp answered ·

What I want doesn't exist. What exist is a defined (could be self defined) profile, but what batterylife does is changing the cutoff voltage depending on the type of charge the last day so it isn't fixed. This is what I meant. I want to use battery life but with the inital start cutoff to be self defined.


In the Code you can set it up as variable and then give it some default value which can be changed.


If the first cutoff should be @23,6V in a 24V system and the weather conditions actually in western germany it would take ages to fill the battery's. The function as it is, is fine with variable cutoff depending on conditions, but it could be better with the pissibility to Set the inital start point to a self defined value.

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