What happens if AC is on (Fridge connected) and battery is emptiy befor it's recharged next day (PC+Sun)


I would like to know if the AC200Max will restore AC output automatically, if it shuts down due to an empty battery during the night.

Once day day starts, the sun comes out, and the battery is being charged: Will it fall back to the previous state, in my case activated AC&DC-output?

I have a fridge (AC) connected. And in case the battery is empty, the fridge will be OK for a few hours, as long as I can be sure that the AC200MAX will turn AC back on, as soon as the battery is being charged again, and has a minimum SOC of 5-10%. I can not always be present and manually turn it back on, in case battery was drained.

If AC200Max is turned off at night due to battery drain, it will not automatically resume AC output.
Once the sun comes out and the solar panel is connected, the battery will recharge. However, the machine will not automatically turn on the AC, you can only manually or APP to turn on the AC output

By a firmware update, it should be possible that to give users the option of “fallback to previous state” after battery was drained and battery had been charged back to 5-10%?

This would be two settings, maybe three:
1st: Fallback after Battery Drain? Yes/No
2nd If Fallback active, at which SOC? 5-15 (user sets value)
3rd If Fallback active, recactivate AC only /DC only / AC&DC.

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Sorry, this practice is not allowed.
BLUETTI power stations are not allowed to automatically turn on AC,DC because of the hidden risk of electric shock.


Is it code? Standard UPS allow this.

Have to say, after tjohnma asked the question, I am curious too. Oter systems will do just that.

I am aware that it might be considered a risk, but it could be disabled by default, and the user should be able to acivate it. Or to asked again: Is there any code (law) which prohibits that for Bluetti?

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Sorry, AC200max doesn’t have the UPS fuction.

Currently the machine can only be activated via PV charging.

I’m using the AC300 and having this feature would be a huge plus. @BLUETTI , please consider adding this as an Advanced feature (can be locked by PIN, like advanced Charging Current Setting) because this is a differentiator to other competitors on the market.

would be nice to have that function!

You could use this on ac switch after sun comes https://www.amazon.fr/SwitchBot-m%C3%A9caniquement-interrupteur-programmable-lapplication/dp/B07B7NXV4R/ref=sr_1_1?__mk_fr_FR=%C3%85M%C3%85%C5%BD%C3%95%C3%91&crid=AK04MZ6W70FR&keywords=switchbot&qid=1698661203&sprefix=switchbot%2Caps%2C97&sr=8-1

At your own risk. I use it to start or stop ac200Max

My APC ups died, I want to use my Ac300 for posing my small fig and it would also power my WIFI. so remote swich would not work for me. Also I wanted a small Bluetti for the garage to power my Fiber controller.

I do not have Solar setup the AC300 is being used as a UPS plugged with the device plugged into it.

If we cannot get this funtion, then I will need to get two standard UPS from APC.

Once option?? maybe I could remove the AC and use some sort of AC to DC power conveter like a battery charger (but higher voltage) and feed that into the PV input? so it thinks it has solar charging.
then after the power outage and dead battery, the AC comes on , it would send the xx voltage to the PV input and bring teh AC300 back on. would this work? and would it bring the AC output for teh Bluetti on or would that stay off?

This is a moot point since the Bluetti devices which include UPS functionality also needs manual intervention to turn on AC or DC functionality after battery drain. This is frustrating discovering this after purchasing Bluetti devices that are marketed to be UPS but are missing critical functionality…

All this won’t work.

Bluetti Ac200Max will turn from PV-input after battery is drained, but only INTERNALLY to accept the PC-charge. It will never turn on AC or DC out. And this is the problem which I (and as I see others) were hoping to get solved by Bluetti. Does not look like it.


I don’t see how this will work, if the Bluetti Box did disable AC output due to low battery. As the sun comes up, the Box will charge (but not the additional Batteries like B230), but AC/DC out will remain switched off.

The switch you showed will only work, if Bluetti AC is already enabled if I see this right, so in this case here would be of no use…

I found our the hard way, left fridge running with Solar and well charged battery for a week. The fridge went off for long enough to signal my battery pack to turn off AC due to inactivity and came back to a bunch of bad smells and wasted food… at least i wont get charged for that week of electricty…
Should be an option to keep the AC on or extend the time out duration…

I think you can turn ECO mode off to prevent it from turning off due to inactivity.

I completely agree. Bluetti needs to fix this. Anytime you turn on any device there is a risk of shock, including when you press the on button manually. The power company does not shut off all your equipment when power is lost, any when power comes back on the electric source goes back to its state prior to outage. This software disablement needs reconsideration.

There is a way to get around the problem, it is not simple but doable.

  1. buy an AC DC adapter 24v or more (without exceeding the max voltage of the solar input): and power the solar input of the AC200max with this adapter. You can also use the original t500 charger and you must purchase a DC7909 female to Mc4 cable then the connectors delivered with the AC200max to power the solar input. You then plug the AC DC adapter into your grid. So, if there is a power outage, and the ac200max is empty and turns off, when the mains power returns it will automatically turn the ac200max back on and recharge it.
  2. The second step aims to turn on “AC” or “DC”. To do this, activate Bluetooth on the AC200max and keep it activated. You are recycling an old Android phone that will still be plugged into a charger on the electricity grid. Absolutely turn on Bluetooth. Activate WiFi on this phone if you have WiFi, otherwise install the mobile network (4G, lte etc.). Install “teamviewer host” and the bluetti app on this phone. Leave this phone near your ac200max. Install “teamviewer remote CONTROL” on your phone that you have with you, register (free) and you will be able to take remote control of the phone left at home or in your mobile home, you will be able to remotely launch the bluetti APP on your old phone and turn AC or DC on. You can also monitor the charge level of the 200max. https://youtu.be/CASSRTpIZyA?si=x-JMyh-LSNMqiBQi

2 bis: an alternative to method 2 above is to automate the switching on of AC or DC. You’re still using an old Android phone, with Bluetooth enabled and powered by a USB socket on the AC200max. You install the Bluetti app and the “Macrodroid” app. The latter allows you to automate tasks on your old Android phone. Then you program for example to periodically check “if the phone’s DC power is cut then turn on ac on and DC on on the BLUETTI APP”. It’s a bit tricky to teach Macrodroid how to click the AC then On button in the Bluetti app, but I did it for another automation program, I can help you

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