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stuartpittaway / diyBMSv4ESP32

diyBMS v4 code for the ESP32 and new controller hardware
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Forced charging ? #196

Open deekoowee opened 1 year ago

deekoowee commented 1 year ago

Hi, I was squeezing very last mAh 's from battery. When battery reached 'Battery discharge voltage minimum' setting, Inverter log says 'The battery asked for a forced charge'. Inverter started to charge the battery.

I checked manually the 'Prevent charging', but seems that inverter still charges with ~0,6A. What could cause the small charging current ?

stuartpittaway commented 1 year ago

What state of charge did the battery get to? What inverter/charger?

My sofar inverter charges with 8amps if the SoC goes below 20%

deekoowee commented 1 year ago

I made some 'easter' testing. I run battery down to 14% SoC by 'Prevent charging' setting. (Minimum SoC can be adjusted from 15% to 80%) 'Prevent charging' did not complete stop the charging and that was confusing me. Unchecked the 'Prevent charging' and inverter started to charge with ~9A. Charging continued to 15% SoC. Inverter is Imeon 9.12

stuartpittaway commented 1 year ago

Ok - the "prevent charging" and "prevent discharge" are values which are transmitted to the charger/inverter - if that device choses to ignore the BMS, it can.

So is there an issue to look at here?

deekoowee commented 1 year ago

I looked the pylon_canbus.cpp and found the lines 38 and 39. If I underestand correct, the limitation is set to 0,1A , not 0A ? I don't know, where the rest 0,5A comes. Maybe measuring error ?

stuartpittaway commented 1 year ago

I found if we transmit zeros to either Victron or PylonTech emulation - they treat the values as "don't exist" or worse, they immediately start to discharge the battery at 100% !

What value is the maximum in the "dyn. charge current" box, when the 0.6Amp is charging ?

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