I have a combination of AC200L and B300K set up to charge from solar. Additionally I have connected an AC load that draws 170W constantly. So, when Solar Input exceeds AC load I expect the SoC to climb. That does not happen. The SoC constantly dropped to lower levels despite the solar input has a lot of power going in. Example: I had a power input of 278W over the last 3h. I also had an AC load of 170W over the last 3h. The difference of 108W should have been enough to at least stop the SoC from dropping or even contribute a bit to charge the batteries. In my case the SoC dropped around 7% The individual batteries had a drop of 8% (AC200L) and 8% (B300K). To my understanding this should not have happened in this amount.
Hi @ftrueck, According to your description, the AC200L + B300K indeed experiences relatively fast power drain.
When the AC200L has AC output enabled, its self-power consumption is 18W per hour, while the B300K has a 5W self-power consumption when there is a load.
Apart from the impact of self-power consumption, we would like to know whether the ambient temperature is suitable and whether you have upgraded all firmware to the latest version.
We recommend that after upgrading the firmware, you recalibrate the device and then test again. Do you think this could be helpful?
Hi @BLUETTI_CARE,
Thank you for the reply.
Firmware is uptodate.
Ambient temperature was moving between 22°C and 29°C at any time. Never above.
Today I completely drained the system with a load of 1.1KW and any power input disconnected until the AC cut of and the AC200 beeped.
Then I replugged all power inputs (solar + AC) and let it charge with 980W AC and around 200W solar to 100%. After that I reconnected my AC load and let it run normally. The only thing I changed was the SoC limits in the custom UPS settings. Before the upper SoC level was up to 80%. Now I have set it to 100%. I read a side note that the AC200L can keep discharging for load compensation under certain circumstances.
I have to admit I didn’t understand that fully but maybe I had this case. For the moment it seem that something has improved but I can not tell at the moment. I will have to see tomorrow how the system behaves under my usual conditions with solar charging during the daylight.
Hi @ftrueck, Thank you for providing the detailed information.
Yes, when you notice fast discharging, upgrading the BMS and recalibrating can be very helpful.
We hope this addresses the issue. Looking forward to your test results.