AC200L: What's going on?

My AC200L is doing weird things I do not understand.

  1. AC Inverter draws power from Grid even when the UPS mode is set to Solar Only.
  2. Unit gets stuck (software hangs) in strange ways. The Buttons on the unit do not work anymore, Bluetooth connection stops working. Only if I disconnect everything the unit is responding again. Then I have to shut down and power up again to make it work normally.

I discovered that the AC inverter seems to be hardwired in some way to the grid. The setting to use charging from the grid is ignored, so there is always a drain from the grid. I verified this with a wifi smart plug that I plugged in my wall socket and the AC200L in that. When I turn of the AC inverter the power draw from the grid stops. The power draw is not equal to the connected AC load. The grid power draw in the app is shown as 0W. The actual power draw is around 90W and the AC Load is around 157W. PV input is 257W.

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I’ve just posted something similar too, although I do not have PV.

Thank you for replying. I guess you also have an AC load running on the AC200L? Did you try to turn of the AC inverter? If yes, you might experience the same as me: As soon as you turn off the AC inverter, the Grid usage goes to 0W. For the moment I use a Smart power plug (tasmota) to turn off grid for my AC200L to get true offline usage with my UPS settings.

Yes, i thought of using smart power plug, but there is 1 huge issue with this approach (and 1 minor one):

  1. When grid it is off by timer on smart plug and station is discharged to SOC Low, it will not switch to use Grid, will drain to 0 and everything will die. So if one day you use additional kettle for several times or played GPU-demanding videogame… it’s really bad.
  2. It can be turned on/off by timer, but it cannot be turned off when the station is charged (to 100% or SOC High). So the rest of the night it will remain plugged and drain from grid (but it might be not so bad, cause costs are low anyway).

I use homeassistant for that.
I use the HACS integration BluettiBT. With that I monitor the SoC. If SoC falls below 20% or time is after 10pm (low price time in my area) the power plug gets turned on. Only downside is: my AC200L seems to crash randomly and bluetooth gets disconnected. This i could not fix yet.

Is it this one? GitHub - Patrick762/hassio-bluetti-bt: Bluetti Integration for Home Assistant
I don’t have a server to run it on, unfortunately, except my router, which has only Python 2, so it might require a lot of work ((
Still, can you please share your script for the mentioned behavior?

As for crashes, do you mean when using the library, or the station crashes even when not used through the API?

With crash I mean: The AC200L becomes partially unresponsive. Buttons on the unit do not react, Bluetooth does not connect. WiFi seems to still work. but the BluettiBT can not use that.

Regarding the integration: Yes this is the one. If you have no server: try a raspberry PI works good with homeassistant.

I’ve just understood another huge issue with smart power plug approach, that cannot be fixed by HomeAssistant:
3. If I plug more consumers (e.g. 3000W) than station’s power (2.4 kWt), with grid connection it will just take 600W from the grid, but when grid is disabled by the plug station will shut down (after it’s short overload timer).

Not sure if 3KW i a good idea for continous use. This might be too much for the inverter over time. In that case you should probably upgrade to a bigger model or get a second AC200L.

I think I understand better now what is going on.
If I check Input side (grid) and output side (load) in the bluetti app I see that the values for Voltage and frequency are exact the same.

This means: The inverter couples inductive or capacitive to the grid to synchronize Volt and Frequency. For this it needs a small dummy load present to the grid to have a current flowing that can be monitored. My tasmota plug shows a relatively high current flow but a very low power factor (aprox 0.2). This means the grid usage we see is only for synchronizing to the grid itself. I can further confirm this when I disconnect the grid (aka turn of tasmota plug). Then the Voltage and Frequency deviate slightly from the grid. Bluetti also mentions a short switch over time (aprox 22ms) in USV mode which resembles the ramp up time of the internal generation of voltage and frequency.

Having said that I think in my case it works best to just use the tasmota plug to disconnect the AC200L from the grid during high cost periods (during the day here) and reconnect it in the night to allow re-charging of the battery, which is my original use case. It is sad that bluetti seems to have no control switch to disable the dummy load but I guess this is part of how the unit is designed. That way my solution should work for me for the moment. My other issue with the unit becoming offline for bluetooth: It seems the way the HASS plugin is connecting to the AC200L seems to cause trouble. I have switched to permanent open connection and this seems to have fixed the issue so far.

@ftrueck I’m not so good with electrics to understand this, lol, but do you think such design flaw/decision can be fixed with the firmware update, or is it how hardware is implemented and nothing can be done?

@snmya that is a really good question indeed. Unfortunately I have no answer as I did never do a hardware analysis on the device. If bluetti implemented in its hardware design the corresponding necessary features, it could be possible to include this in future firmware updates. If the design of the hardware does not include this then no.
@BLUETTI_CARE: can you ask your developers if they see a possibility to tie dummy load to the charge/discharge schedule? It would be enough to disable the dummy load in discharge setting and enable dummy load in charge setting (schedule). If you want to be extra fancy: Do an additional control switch in advanced settings called “Solar autonomy mode” which will tie grid input dummy load to charge/discharge schedule in UPS settings.

Hi @ftrueck, It seems that after switching to “permanent open connection,” the issue has been resolved — is that correct?

When you mentioned, “If I check the input side (grid) and output side (load) in the Bluetti app, I see that the values for voltage and frequency are exactly the same,” — that’s expected. When using grid charging and there is an active AC load, the system enters bypass mode, and the voltage and frequency will sync exactly with the grid.

If your goal is to disconnect from the grid during non-charging periods, but still allow charging at other times, you’ll need to control the charging power by limiting the current. A display of 0W means the input is 0W, which already meets this objective.

When you mention the “actual power draw is around 90W,” could you let us know how the cables are connected, the power rating of the load, and where the power meter is located? Ideally, please record a short video, upload it to a cloud drive, and share the link with us — that will help us replicate the issue more accurately.

Currently, we do not support the use of a “dummy load” as you described.

Many thanks to snmya for the input and discussion on this matter.

@ftrueck Hello! A followup question about HA: can it work with Bluetti via WiFi, not Bluetooth? If not HA, maybe there’s another lib that can do that (like query SOC at least)? Just found out that Bluetooth module present but not accessible on my router ((

Unfortunately not. I did not find any project that uses bluetti API via web to access the values.

Unfortunately the unit is again not accessible via bluetooth. I do not know what is happening there but the unit simply refuses to react to bluetooth at all. I can not even determine specific conditions that lead to this loss of connection. It just happens randomly it seems.

I hope my drawing makes things a bit more clear.


What I tried to describe is: AC200L shows 0W grid usage while tasmota plug shows 90W power draw with PF of 0.2. That means the AC200L is drawing power from the grid but the app shows 0W. The problem I have is: the 90W are actually billed because they are Active power which count as normal power usage. It is just like plugging in a 90W light bulb for 24/7. When the bluetti app shows 0W, I have to assume that it does not draw ANY power from the grid. The reality in my case is different: It draws 90W 24/7 which is too much and not acceptable. I refered to a dummy load because I assume that is how the inverter is synched to the grid when he is in bypass mode. If this is not switchable or not even possible to disable bypass mode that is actually very unfortunately.

Hi @ftrueck, Regarding the issue of Bluetooth connection failure, please troubleshoot according to the following steps.
Here are some basic troubleshooting steps for connection issues:
Bluetooth Connection Troubleshooting:

  1. Check Device Settings:
    ○ Verify if the Bluetooth function on your device is enabled. Long press the AC+DC power buttons to check if the Bluetooth icon is displayed on the top right of the LED screen. If not, switch to the P06 page using the DC button and press the AC button to enable the Bluetooth function.
  2. Restart the Device.
  3. Restart Bluetooth:
    ○ Turn off and on the Bluetooth function on both the device and your phone.
  4. Offline Mode:
    ○ Log out of the account and try offline mode to directly connect via Bluetooth. If it connects, the issue may be with the phone signal.
  5. Unbind and Rebind:
    ○ If the device is already bound, unbind it and try reconnecting.
  6. Reinstall the App:
    ○ Try reinstalling the app.


As for the problem of power loss, it indeed seems to be quite high. We will conduct tests and try to reproduce the issue, and we will give you a reply next week.

When I have the Bluetooth issue my AC200L becomes unresponsive to button presses. It only starts reacting again when I disconnect PV, Grid AND the B300K that is also connected to it.
I have no idea how this makes the device unresponsive but I can not press any button on the device until I disconnect the mentioned things. Then I usually power off the AC200L and then I start it again and the issue is solved.

Regarding the power loss tests: Just to make sure it does not get lost in conversation: My AC200L has a B300K connected to it. Maybe this is relevant for the tests, but I do not know for sure.
Anyways: Thanks for your help, I highly appreciate it.

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Hi @ftrueck, You are welcome, it’s my pleasure.
This kind of issue is indeed rare. We still would like to know your firmware version, as it will help us with testing and reproducing the problem. We look forward to your reply.