System is AC500, AC300, one B300S, two B300’s. 3KW SMA AC inverter house rooftop system plus 4x400 watt Carport modules feeding DC to Bluetti AC500 or AC300. AC500 and B300S added later. Two T500‘s charge batteries directly when excess SMA inverter output exceeds 1000 watts.
After adding another B300 to the AC500 (shut down AC300) I have intermittently Error 104. “BATT Power Low”. This did not occur with same configuration last year. All three batteries were between 25 and 79%. One B300S and two B300’s.
Since this occured it has happened three more times - usually once a day. Everytime the batteries have sufficient charge. I reconnected all battery cables in new positions.
The last thing I had done before all this started was to add one more B300 from the AC300. I removed this battery from the AC500 to see if the error still ouccured. It failed again.
BMS Version
Battery Pack 1 B300S 1022.09
Battery Pack 2 B300 1014.16
Battery Pack 3 B300 1014.13
AC500
DSP Version 4047.06
ARM Version 4048.02
HMI Version 6052.07
Any suggestions? The troubleshooting in the App does not address mixed battery installations.
Hi @Wuastr, We are a bit confused by your description.
We’d like to know how many batteries are connected to the AC300 and how many to the AC500?
If possible, it’s best to keep the AC500 inverter symmetrically connected with an even number of battery packs. Ideally, the AC500 should be connected to at least two battery packs.
Could you try again? Please connect two battery packs separately to the two Battery Expansion Ports on the AC500. Does this resolve the issue?
We’d like to know how many batteries are connected to the AC300 and how many to the AC500?
Depends. This summer it was one for the AC300 and two for the AC500. No issues except uneven charging. The AC500 seemed to ignore the B300 #2 at times. I had to charge it with the T500 directly.
I changed to 3 batteries for the AC500 and the problem started - BUT only after a long period over 12 hours. Occurred twice again. Usually after one day.
Actually the very first error message was AC output short circuit with shutdown. There was of course no AC short. Reconnected cables, Shut off and restart seems to have resolved that issue.
Removed extra battery #3 so only two were connected to AC500 ( previous original setup with no issues). Except now with just two batteries it did fail again.
If possible, it’s best to keep the AC500 inverter symmetrically connected with an even number of battery packs. Ideally, the AC500 should be connected to at least two battery packs.
Well that an even number of batteries is required or recommended is new information to me. Certainly not in any sales information that I have seen.
Please connect two battery packs separately to the two Battery Expansion Ports on the AC500. Does this resolve the issue?
I have only three batteries so impossible to connect two pairs, if that is what you are asking.
Today I ran just one battery (B300S #1) with no faults. I am running again tonight with one battery (B300 #3). If that works okay I may have an issue with battery #2 .
Your error has nothing to do with how many batteries you have connected and in what order.
These are all connected in parallel in the AC500/AC300.
That’s why they are so thick!
I have 6 batteries connected to one connection on my AC500, one after the other.
They are all stacked like a tower… the AC500 is at the top!
There are 3x B300, 1xB300S and 1xB300K.
Everything is stable.
You have to calibrate them after connecting them though!
By calibration you mean take to zero and 100 % charge?
In any event the battery #3 and battery #1 combination failed after 2 days. I tried the old setup with Battery #1 and Battery #2 and so far stable. Without sunshine it takes time to do AC On situations due to no charge.
I will probably go back to what I know worked. AC500 with B300S and B300 and use the AC300 with second B300 (Battery #3) for running the washing machine.
One of the units has an intermittent issue methinks. Unequal charging, stray faults, etc.