Hi Thank you for getting back with a quick response.
Ok I went into the App and saw ‘Firmware Upgrade’ and BMS Version was highlighted in blue
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In the ‘Battery Information’ the ‘Check For Update’ button was available for all 4 batteries. Both B300 batteries were on Version v1014.10 and so when I tapped on these a dialog button/info box popped up and stated ‘No new firmware version’
Next I checked the ‘Check For Update’ button for the two new B300s I noticed one was running version v1022.09 whilst the other was running version v1022.08. The prior came back with the same dialog button/info box pops which states ‘No new firmware version’
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However the B300s on v1022.08 came back with the following screen
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I followed this to the next screen
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I followed this instruction and disconnected the other batteries and left the B300s running v1022.08 and this time the above screen was omitted and the firmware update started.
Now then I didn’t expect the following. As the firmware started I heard some sort of ‘pop’ (like a capacitor blowing) and the AC500 and the connected B300s shut down. Following this on starting up the unit the B300s would turn on but the round ‘On’ button was flashing and none of the charge status 5 small green lights were illuminated
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Now also on the AC500 all these new following error messages simultaneously came up
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Following this I disconnected the now defunct battery and checked all the others and all the cables. I left the defunct B300s turned off for some three hours and then turned it on again and I can confirm it is now a very heavy paper weight and so I will need to arrange a return.
Now then I had started another thread on this forum relating to how many actual B300 batteries can be connected to the AC300 when connecting both B300 & B300s as I was originally given the wrong information as a backer on Indiegogo which stated 2 max when actually Bluetti now states ‘If the b300 is connected first, then to the b300s, AC500 is able to identify six battery packs.’
So as I have a spare B300 I have connected this (in replacement of the now defunct B300S) on the same chain port as the other two B300 in serial, so I now have 3X B300 in total. I then connected the remaining B300s v1022.09 (so no firmware update needed) to the second chain port. All fine and working - except the same original problem presents itself when the unit reaches fully charged between 98% and 100%. At this point I hear again the ‘Alarm’ buzzer/beep every time and the Alarm error code 098.BMS Over Voltage displays in the Alarm screen.
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Agggghhh!!! So I’m now one B300s battery down following precisely the firmware update instructions and still have the same issue!
Where do we go from here?
Your assistance is very much appreciated
Kind Regards
Dean