Also could you comment on the table I presented and the fact that the main panel SOC reading didn’t show the correct value until I changed the power cable connections. I.e. I switched them around to see if it would make a difference and it did.
Hi @bluetti_jebrroprotonmailcom, In our previous response, we provided the most suitable method for testing capacity. It would also be very helpful if the customer uses additional plugs or power testing accessories.
When the AC300 is without load and the AC output is turned on(DC output turned off), the self-consumption is 43.5W per hour, and the self-consumption of each B300 battery is 2W per hour.
We reviewed the screenshot of the table you provided and noticed that the total energy displayed in the yellow section is identical to that of Pack 3. We suspect that Pack 2 is not correctly connected or locked, which is why it has no impact on the total energy. Please try reconnecting and locking it again.
Additionally, please make sure to use the left-side method to connect the two B300 batteries in a symmetrical manner.
If the result remains the same after correctly connecting the batteries symmetrically, please swap Pack 2 and Pack 3. If the result changes, it indicates a fault with one of the AC300’s parallel ports, and repair will be necessary.
Update
-AC and DC output has been off and remains off.
-ECO mode is OFF and has always been OFF.
-Connections to batteries has not been touched. Recall previously that I was able to get home screen SOC to report correctly by switching the power cables. I am 100% sure nothing has been disturbed.
-System SOC was reporting 17% at 8:17am on 1/9/2025.
-Low SOC was result of numerous overcast days which greatly reduce PV charging.
-Sunny day all day 1/9/2025.
-SOC reported 49% at 6:15pm on 1/9/2025.
-1/10/2025 AC300 is unexpectedly found to be completely off. ECO mode is OFF and was never turned on.
-System was powered on.
-SOC reports as 47% at 6:50am on 1/10/2025 on home screen.
-BP2 is 95% charged. BP3 is 100% charged.
I would like to know your thoughts on this situation?
I have a second AC300 as I have been preparing to setup a split phase system (I already purchase the components) for my shop power and add two more batteries. Due to the various issues I am having with the equipment I am in doubt as to whether to continue with Bluetti products to do this. If it turns out that my battery capacity is low (which should not be the case because the system isn’t that old and it has very light usage) and the system turns off unexpectedly or reports SOC correctly and then out of the blue reverts back to an incorrect value then this would pose a lot of problems to deal with.
I will inspect the connections very carefully including looking at the cables to see if there is any indication that a loose connection exists. I don’t expect to find this as I was careful to fully install and lock the cables. Again the system was completely untouched. I will then swap out the existing AC300 with my slightly newer, unused AC300 to see how it affects these issues. I am not going to update the firmware at this time unless you know of a critical reason I should do so. I still need to check the cabling arrangement for the symmetrical configuration you mentioned. thank you.
Related question. If the cable isn’t locked then the BP SOC for that battery would show as unconnected correct? You indicated earlier you thought I hadn’t locked one of the battery cables.
Hi @bluetti_jebrroprotonmailcom, We believe the issue might be caused by the cable not being securely locked. You can try using a different cable to test, which will help rule out any faults with the cable itself. If it’s confirmed to be a cable issue, we can arrange warranty repair services for you.
As for the AC300 shutting down automatically while still powered, we guess this could be related to the ambient temperature. Can you confirm there were no loads connected? If there were no loads, this could also lead to an automatic shutdown. Please check the Alarm History for any past error codes.
Yes it is most likely the power cable that is responsible for the SOC misreporting on main screen. I will swap the two cables I have and see if it follows the cable. This morning, 1/13/2025 around 8:30am EST I observed the main screen SOC showing 49%. Thinking this is the suspected cable issue I carefully unlocked and relocked the switch on the cable several times without moving the cable itself. This resulted in the SOC on main screen again reading basically 99-100%. So I can confirm this is responsible for the SOC reporting issue on my system.
It seems odd that switch can lock and the firmware recognize it and then if the switch somehow “unlocks” electrically overnight, but does not move mechanically, the firmware doesn’t catch the changed state of the switch. Should it not still read 100% because it only recognized one (1) battery now being connected instead of two? I think you have a firmware issue here to go along with the cable problem. I don’t think it is reacting properly to the switch being mechanically in the lock position but electrically in the unlocked position.
Is there a chance this problem could be with the battery receptacle where the cable plugs into?
I will know more when I swap the cables. After that I will try and look at the battery capacity. Is there not an easier way to report battery capacity then for me to discharge my batteries completely under high load (>1000W)?
thank you
I am replying to the second portion of your response:
The AC was turned off and there were no loads present. There was no indication of an alarm from the main screen.
The ambient temperature doesn’t drop that low. The lowest I’ve seen is 30deg F.
Can you explain why the ambient temperature would shut down the AC300?
thank you
Just occurred to me that to do the battery capacity test I don’t want the intermittent power cable connection issue to affect the result so I need to resolve that first before I move on. How do I go about getting a new power cable for the B300 battery? thank you.
Hi @bluetti_jebrroprotonmailcom, Yes, the cable needs to be securely locked for the AC300 to communicate with the battery pack correctly.
Please test whether the issue is caused by:
1/ The cable is not being properly locked.
2/ A problem with the AC300’s battery connection port.
3/ A fault in the cable itself.
You can cross-test by connecting two batteries to each parallel port separately to identify the problem.
To test battery capacity, connect a high-power appliance for one hour, calculate the hourly load’s rated power plus self-consumption, and check the specific SOC decrease to estimate the total capacity. It’s not necessary to fully discharge the battery.
The AC300 has pre-set charging and discharging temperature ranges. Refer to the product information in the screenshot for details. The temperature readings are based on the actual measurements by the AC300, which may have slight deviations. Additionally, the internal cell temperature differs from what you may feel externally. For optimal performance, we recommend storing and using the unit in a suitable temperature environment.
If you confirm the issue lies with the connection cable, please contact customer support for assistance. You can also send a message to us with your order details and email address, and we will arrange further support for you.
Is the discharge formula given previously the number of hours before the batteries are depleted? What are the units? It looks like the units are hours?
Hi @bluetti_jebrroprotonmailcom, Yes, you are right, it was about the running time, the units are hours.
Running time = Battery capacity × Depth of Discharge (DoD) × Efficiency (η) ÷ Device Wattage
I do have a problem with one of the power cables. Can you help me get the ball rolling to get a replacement?
thank you
Jeff
Hi @bluetti_jebrroprotonmailcom, can you contact us via private message, and provide the order information?
Then we will apply for the cable for you.