I have an AC500/B300s, connected to two 400W PV panels in series.
I notice that in the morning, the AC500 does not turn on at dawn when the PV power starts. Even when available PV is >70V and >100w available, it just never turns on.
However if I unplug & replug the panel, it does then turn on and start to charge, so it seems this issue is that it does not start from the very slow rise-time of the power from the sun rising.
I have latest firmware DSP 4047.30, ARM 4048.04, HMI 6052.03. I’ve tried various UPS modes with no difference.
There is a secondary issue, which I believe has been previously reported, that the AC500 does not turn off even if the PV input power is below the unit’s internal draw, causing the battery to be discharged unnecessarily. It is not even possible to turn off manually if there is the slightest voltage on the PV input -surely it would be possible for this design flaw to be fixed in firmware ?
Seems a bit ridiculous to need a special version to fix an obvious flaw - @bluetti_care why isn’t this fixed in the main release, and if I have a special FW, does this get lost if I update FW in the future?
@mikeselectricstuff Are you unable to activate via PV in the morning, or are you unable to activate throughout the day?
Could you try again to see if PV can activate charging when the sunlight conditions are ideal?
The problem is that the AC500 does not wake up automatically when the sun rises.
If I disconnect and reconnect the PV input, or switch the AC500 on manually with the button, it wakes correctly and starts charging.
It seems that the issue is that the very slow increase in PV input from zero as the sun rises does not wake it up.
@mikeselectricstuff
SN recorded and one more thing to confirm with you:
Does the machine activate charging normally after re-plugging?
What is the PV voltage and power detected by the machine after normal charging?
I did some more testing.
What seems to happen is - at dusk, the AC500 eventually turns itself off - not sure how long this takes but probably a few hours. (This is with AC and DC outputs turned off. )
At dawn when PV returns, it does not turn on, and it is also not possible to turn on using the power button on the AC500 or by disconnecting/reconnecting the PV.
In this state, only the button on the B300S will wake the AC500.
Once it has been turned on via the B300 button, it can then be turned on/off with the AC500 button and the PV input .
So the issue appears to be that in the absence of PV input, the AC500 will eventually enter an “off” state, which can then not be exited via the AC500 button or PV input.
This may be associated with a low SoC, I have seen it behave like this at 0% and 11% SoC, will try it again at a higher SoC
Some more data - the issue appears to be what happens when the AC500 turns itself off - this happens many hours after the last PV or grid input or user interaction. Does not appear to be SoC related - last test was at 37%.
In this state, it is not woken up by PV input, AC500 power button or grid input - the only thing that turns it on is the power button on the B300.
Maybe I am missing something so this might not apply, but I’ll mention it anyway because we’re all in this together. I have an AC300 and my manual states, that if I am on eco mode that the unit will shut off after a few hours if there is minimal output. Also, if the unit shuts off i would have to manually turn it back on, because you can’t do that by the app (admin can you fix that?). i have stuff constantly plugged in.
Maybe you just need to adjust that setting.
Again I’m throwing stuff against the wall to see what sticks.
I am curious though, how much input current does it take to kickstart the AC500?
I had something similar with a D300s, the unit was grounded and that could have been a cause according to support:
If the customer connected a solar panel grounding cable to the grounding of D300S,please disconnect them.
It may solve the issue.
My guess would be: potential difference between grounds (if panel and ac500 are grounded separately), and if they’re connected to the same ground, a ground loop perhaps.
Panels are not grounded (this is a tempory setup) .
I found that if I leave the DC output turned on, the AC500 does not go to sleep.
This provides a workaround for the issue, though doesn’t fix the underlying problem.
This is normal, it should be that you have ECO mode turned on. Or can you see if there is an error history, did it report an error that caused the shutdown?
Is there any power when you turn it on? Or is it that one of the batteries is dead, if the power is off because one of the batteries is dead, it really won’t activate.
Open circuit voltage is no needed, the tech team needs to know is the machine input voltage when you can charge it, click on the PV input icon one.
In addition to the SN you have already provided, could you also provide the software version of the battery pack? How many B300 and B300S do you currently have?
By the way, does the machine have a load connected? Normally, the machine shouldn’t shut down without a load. If there is a load, what is the power of the device?
Eco mode is off. No alarms in history, no load.
One B300S BMS version 1022.08.
After it has powered itself down, the battery SoC makes no difference - it still doesn’t turn on via either the AC500 button or PV input. Only the B300S button will turn it on
Something else I noticed - I have set custom UPS mode, and Battery SoC low to 30%, yet when I connect an AC load ( car charger), it discharges to 0% before shutting off.
@mikeselectricstuff Thank you for your detailed description. Based on your description, the technical team believes that the firmware cannot completely resolve your issue, and your AC500 unit needs to be returned to the repair station for maintenance.
Please email the support team for further communication on the return for repair based on my response.