ESS permanently changing between charging and discharging when minimum SoC is reached (Pylontech)

Hi,

in the past I was wondering, why my SoC was falling 1% every 1.5 hours when minimum SoC was reached. The reason was peak shaving being activated always. I’ve changed this to “only above minimum SoC”, but now I have the problem, that when ESS is discharging and minimum SoC is reached, it will start charging immediately with around 400W slowly dropping to 0W. Unfortunately after a few seconds, SoC will go up by 1% and discharging again starts. After a few seconds it is falling again by 1% and charing immediately starts. As a work around I added a function to Node Red which sets peak shaving to always on when SoC is above minimum SoC, to “only above minimum SoC” when SoC is below minimum SoC and when SoC reaches minimum SoC it will change it to “only above minimum SoC” with 2 minutes delay. This seems to fix the issue.

Maybe this is only an issue with Pylontech, but hopefully Victron can change this behavior in their software with some hysteresis or delay.

Workaround deployed at 06:27:

Workaround:

What ESS state code does it show on the remote console when this happens?
ESS itself does have a hysteresis and its more than 1%.

It’s possible for you to hit the conditions for a bug in the firmware to behave.
I have something similar and Victron said that will fix it.
See here: https://communityarchive.victronenergy.com/questions/253503/ac-input-control-issue-battery-conditions.html

I found the problem. It was related to a Node Red function that set State. I did this because State sometimes jumped to 5 even though I don’t want to use “with BatteryLife”. I don’t know why this happens, I first noticed it after I put my MPPT into operation. My own logic didn’t take all eventualities into account. I have now simplified it and the ESS no longer switches between charging/discharging.

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