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inigodu avatar image
inigodu asked

Active SoC stuck at 80 %

Hi! I have a question regarding the functioning of the parameter 'Active SoC limit' that can be found in the ESS. While in mode 'Optimized (with BatteryLife)' I started playing with the different parameters to test the installation, and in particular with the parameter 'Minimum SoC (unless grid fails)'. At first, both 'Minimum SoC (unless grid fails)' and 'Active SoC limit' had the same value, but after increasing the value of 'Minimum SoC (unless grid fails)' up to 100 %, the 'Active SoC limit' became stuck at 80 %.

I would like to know what does this parameter 'Active SoC limit' really mean and what's the functioning behind, so I can have a better understanding of it once I change the value of 'Minimum SoC (unless grid fails)'. I have already read the ESS Manual but it is not very clear to me yet.

I would like to add that my installation works mainly disconnected from the grid except in a few occasions that it is connected for short periods of time. I don't know if that has anything to do with the system recognizing this and, thus, trying to set a high value according to this characteristic.

Thanks!

ESSSOC
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4 Answers
Paul B avatar image
Paul B answered ·

Optimized (with battery life) is for lead acid batteries

are you using Lipo if so then change to Optimized (without Battery Life


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Hendrik Coetzee avatar image
Hendrik Coetzee answered ·

It might be worth reading the victron docs (again?):

https://www.victronenergy.com/media/pg/Energy_Storage_System/en/controlling-depth-of-discharge.html#UUID-af4a7478-4b75-68ac-cf3c-16c381335d1e


Specifically, the following might be relevant to BatteryLife:

  • Certain lithium batteries also need to be fully charged regularly in order to balance their cells. This includes the Victron 12.8V lithium batteries, for which it is mandatory to enable BatteryLife.

  • In case of mains failure - having no spare energy available from the batteries to power the loads defeats the whole purpose of having a battery back-up.


I know that my BYD needs to hit 100% (or 10%) in order to calibrate the BMS. If I do not take steps to ensure this happens, SOC get weird (and I see strange voltage drops during the evening, after min SOC has been hit).


The main idea of BatteryLife (and the Active SOC Limit) is to automatically get your battery back to 100% during daylight hours, in a way that adjusts (slowly) to environment/situation.


From the docs, it is also clear that this is not exclusively for lead-acid batteries, but lead-acid installations will probably see the most benefit (in preventing damage).

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airbag888 avatar image
airbag888 answered ·

Sorry for raising this months later but if I understand correctly, there is no way to influence the active SoC?
My situation is that I produce a lot more than I can store (yes I should get a bigger or more batteries eventually)
So by the time it's 10am my batteries are already full from the 20% where the min SoC limit is at.
My concern is sometimes I want to raise that min SoC say to 40% just to have some more reserve on days where I suspect there may be a powercut. Then close to the morning I'd push the SoC limit back to 20%.
I was thinking of doing that via MQTT using my home assistant setup but each time I change the SoC limit the Active SOC goes up to almost 100% and takes days to go down to 20% which is kind of silly...

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solarlion avatar image
solarlion answered ·

Have the same Question.

I now how the automatic minimum SOC Works from the manual, but sometimes I don’t want to wait 12 Days for it to fall by 5% a day from 80% to 20% when I know there is enough energy tomorrow. So I look for a way to manual adjust this value and then continue by this ESS algorithm to skip wasting 12 days’ worth of energy.

Is there a MQTT endpoint to write this value?

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nickdb avatar image nickdb ♦♦ commented ·
Just change modes to without batterylife and raise the minimum soc as necessary.

Outside of European nations and their iffy weather and daylight savings, I just leave it disabled. Lithium can survive a few days without being fully charged daily until weather improves. Batterylife is just too lazy to be any good outside of the northern hemisphere. It is far easier to adjust the minimum soc.

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solarlion avatar image solarlion nickdb ♦♦ commented ·
Thank you for the tip. But unfortunately I am out of the north :(. So really want to use it and think its a good feature. Its just for the start because its a new system and I dont want so many days to wait until it is operable.
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thanar avatar image thanar commented ·
Having the exact same issue. Just a bit different. I have been using BatteryLife with my lithium installations, and I find it very useful and well-thought. However, today (while the BatteryLife SOC was at 45% trending to 40%), I accidentally adjusted the minimum SOC to 80% and now the BatteryLife SOC jumped to that value. There should be some way to set it to a specific value and then let it do its thing.
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solarlion avatar image solarlion thanar commented ·
There is a way to do so: You can set both values minSOC and SOCLimit over MQTT or Modbus. The build in algorithm then continues at the newly set value.
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thanar avatar image thanar solarlion commented ·
Would it work over nodered?
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solarlion avatar image solarlion thanar commented ·
yes
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