Hi,

I am new to this, so please forgive a stupid question.

I have a 3KVA Axpert type inverter set to charge the battery at 20A from the utility (programme 11) which I have just increased to 30A for the first time. I can see on the battery app PowBank the actual charge current. When it started charging after the last load shedding, it started at 30A as expected, but at around 30mins in, the fan slowed down so I checked the app and it has been charging at between 16 and 19.5A since. Is this normal? Or is this a function of the bms, or a heat dissipation issue? Any thoughts will be appreciated. 

Thanks

Edited February 26, 20233 yr by Brad Dann
Changed '16-18' to '16-19.5'

3 hours ago, Brad Dann said:

Hi,

I am new to this, so please forgive a stupid question.

I have a 3KVA Axpert type inverter set to charge the battery at 20A from the utility (programme 11) which I have just increased to 30A for the first time. I can see on the battery app PowBank the actual charge current. When it started charging after the last load shedding, it started at 30A as expected, but at around 30mins in, the fan slowed down so I checked the app and it has been charging at between 16 and 19.5A since. Is this normal? Or is this a function of the bms, or a heat dissipation issue? Any thoughts will be appreciated. 

Thanks

I am not sure what it is you worried about. Do you wish for the charge  cycle to be shorter or longer.? 

The inverter only puts back what had been taken out during loadshedding. When it becomes nearly fully charged the current will start dropping. 

Thanks for replying. I am wondering why even though the inverter is set to charge at 30A, it is not, as I stated above. Yes, I want the charge time to be shorter, which is why I have increased charge current from 20A to 30A

6 hours ago, Brad Dann said:

at around 30mins in, the fan slowed down so I checked the app and it has been charging at between 16 and 19.5A since. Is this normal?

Yes, it's normal for the charge current to reduce as the battery voltage approaches the bulk/absorb voltage setting.

Is the battery voltage approaching the bulk/absorb voltage setting?

Thank you. That makes sense now that I understand that function of the BMS. I can also confirm that, because after the first 2 hour loadshedding, the 200Ah LifePo4 battery was down to about 67%, then charged at around 30A for about 30 minutes before dropping. It was down to around 70% after the second and charged for a few mins before dropping. 

Thanks for taking the time to help.