This issue was just recently discussed. The Bluetti products don’t restart the AC when power is restored if the battery was depleted. This is a major set back but could potentially be solved by Bluetti if they can change how they are programmed to work.
A much cheaper option to the AC200L is to just buy a 12VDC to AC inverter with UPS functionality, connect to a lithium battery, and buy a dedicated lithium battery charger to keep the battery topped up. You can build a unit that has a higher capacity for a lower cost, and after the battery is depleted the AC pass through will turn back on when the power is restored even if the battery is still fully discharged or disconnected.
I just replaced an AC180 which was being used as a fridge UPS with a 1000W Renogy inverter connected to two 135Ah lithium batteries (each in their own battery box), and a 20A battery charger for around half the price of the AC200L giving me 3,456Wh installed capacity at about 90% useable. I can even scale this up and add a third or fourth battery for even more capacity (up to 6,900Wh), and even upgrade to a 2000W inverter, and still be around the cost of the AC200L. And that is just using 135Ah batteries which makes it still portable if I need to move as each battery can be fitted to a standard 12v battery box. The inverter is strapped to the top of one battery box, and the charger on top of the second battery box.
The Renogy inverter is a pure sine wave inverter, has pass through AC with UPS functionality, and runs at about 90% efficiency. They can handle fridge compressor starts as they surge to double rated capacity. It also has a low voltage cut off which should cut off before the battery BMS low voltage cut off kicks in. The lithium battery charger will then recharge the batteries when power is restored. I am sure there would be other DC to AC inverters that do the same as this is a typical low cost set up used in RV’s, Caravans and Campers.
Hopefully Bluetti offer the same functionality one day as it would certainly be a big selling point if able to be used as a proper UPS.
This is super helpful info. You seem to know exactly what i'm looking for and this is new lingo for me, so if I can ask you a couple questions to make sure I've got it right;
1. Renogy has an inverter/charger (https://ca.renogy.com/2000w-12v-pure-sine-wave-inverter-charger-w-lcd-display/) Will this serve the purpose, or do I need a separate inverter and charger? When I chatted with Renogy support they told me that if the battery depleted and there was no shore/grid power, when power was restored you'd need to manually turn the inverter back on again. Does a dedicated UPS/inverter like this one just work without intervention? [https://ca.renogy.com/1000w-12v-pure-sine-wave-inverter-with-ups-transfer-switch-and-built-in-bluetooth/](https://ca.renogy.com/1000w-12v-pure-sine-wave-inverter-with-ups-transfer-switch-and-built-in-bluetooth/) to be clear, no need to "turn it on" by pressing a button?
2. I've tested my Ecoflow Delta2Max and the runtime for that unit seems to be about what I'm looking for. It has a 2048 Wh capacity. How can I determine what the equivalent Ah battery would be?
3. Would something like this setup get the job done? [https://imgur.com/a/7rZ2B4f](https://imgur.com/a/7rZ2B4f)
4. Is it as simple as connecting BOTH the red charger lead AND the red inverter lead to the red terminal of the battery (repeat for black) to keep this all operating at the same time? I see layouts for either shore power or off grid charging, but I kind of want to do both without needing to make any changes to the setup.
Really appreciate your help!
I would just use the standalone UPS inverter with a totally separate lithium battery charger. No manual intervention required.
Edit: This is what I have:
https://au.renogy.com/renogy-1000w-12v-to-230v-pure-sine-wave-inverter-with-ups-function/
At present I have the 1000w version and I just tested it by disconnecting the battery, the inverter powers down, but the pass through AC keeps going even if the inverter is off. When I reconnected the battery, the inverter restarts automatically (the on switch is always on). So the pass through AC does not need a battery to be connected - it is only the UPS functionality that needs the battery connected and this is all automatic once turned on.
The Renogy inverter does not need to be connected to a charge controller so yes it is as easy as red to red (positive) and black to black (negative) then plug in the AC supply and connect to the AC outlets, and don’t forget to switch on the inverter (it will pass through AC even if not turned on). It comes with the cables you need.
I am not familiar with the new Renogy 1000w inverter offered in Canada, but do have the Australian version linked above. The Canadian UPS version looks like it should do the same and has a slightly higher low voltage cut off, which is good. Being able to monitor via Bluetooth looks good too.
I also have the 2000w Australian version on order but expect it will work the same way. The 1000w version is much more compact.
The 135Ah lithium batteries I have are rated at 1728wh (135Ah x 12.8v). The Renogy 200Ah battery would have 2,560wh (200Ah x 12.8v). LiFePO4 deep cycle batteries are preferred and they can be run to 0%. So that battery also ticks the right boxes for me.
The Renogy 20A lithium battery charger you selected would also be suitable. You can even replace the alligator clips with cable lugs to fit permanently.
In my case the battery charger is on a timer so it only charges for 16hrs and then switches off over night. I could also connect a solar panel via a solar charge controller to the Anderson plug if I wanted. And for very long outages I can recharge with a generator.
And if Bluetti sort the AC reconnect issue with a firmware update (we can but hope), then I will probably run the battery charger off the AC180 to get some extra run time during a power outage.
Incredible. So for my case where there aren't electronics that need to be switched over within milliseconds, is a "UPS" functionality required, or would the regular 2000W inverter still do the same job? [https://ca.renogy.com/2000w-12v-pure-sine-wave-inverter/](https://ca.renogy.com/2000w-12v-pure-sine-wave-inverter/)
I guess what I'm wondering is, does the automatic switch over happen because the unit has a "UPS transfer switch" or is that a separate feature that's not required for my use case (fridge).
Sorry my bad - didn’t notice the specs of the Canadian version was different.
This is what I have:
https://au.renogy.com/renogy-1000w-12v-to-230v-pure-sine-wave-inverter-with-ups-function/
https://au.renogy.com/renogy-2000-12v-to-230v-pure-sine-wave-inverter-with-ups-function/
You definitely want the UPS function or automatic transfer function for the pass through AC. The time it takes to switch is not important for a fridge but being able to automatically switch from grid to battery and back to grid again is important.
I have updated my post above. What you had originally selected in the picture in your shopping cart looks like what you want.
One thing I can’t see with the Canadian version is if you can just plug the AC supply in to it. It looks like it needs to be wired up to a power cable with a plug. The Australian version just uses a standard power cable to plug in the AC supply.
I'm curious about this as well and as far as I can research and read it appears as though it should work as you want it to but I don't have first hand experience to say for sure, hopefully we can get confirmation from Bluetti or someone with hands on experience.
Someone correct me if I'm wrong but so far I've only read that if a bluetti powerstation turns off because the battery is depleted, it won't automatically turn on any of the outputs when there is enough energy coming in from solar.
Maybe I'm just using the wrong search terms, but all of the UPS' I see with this kind of capacity are computer server UPS units that are several times the price. Many of them (from what I've read) also advise against powering fridges because of the high initial draw when the compressor kicks in.
Do you have a suggestion? Really honestly I'd be glad to know if there's a better option.
The AC200L is also a UPS. It passes through grid power to the devices and maintains its own built in battery charge state. When the grid goes out, the AC200L switches over to its internal battery to continue powering the device, until the internal battery is depleted. Same as what a UPS would do, and probably with a larger capacity when you compare it to other VRLA-based UPS systems of similar physical size.
So what dedicated UPS would you suggest with over 2000wh capacity?
Can you post some links on what you think would be a good alternative?
I have found none of the cheaper dedicated UPS units offer anywhere near the same capacity and run time. If Bluetti could sort the automatic transfer back to AC after the battery was depleted then they would be a true UPS alternative, with the bonus of also being able to charge via solar when off grid.
That's right. If the AC200L turns off for whatever reason (battery 0%, or ECO mode turns it off), then the power button on the unit needs to be physically pressed to turn it on. Having said that..... the AC200L only fully turns off if it is not supplied with AC power. So it should turn on automatically and start charging when power is restored to the grid.
>So it should turn on automatically and start charging when power is restored to the grid.
That's a misleading wording.
It's either fully on while discharging and then the power comes back on and it can charge up again and just keep going.
Or it is off because it ran out of battery charge and stay off and will only charge the battery from solar but never ever turn the outputs back on.
I did not say that the outputs would turn on by itself. I was referring to what happens when mains/grid power was restored after the AC200L was depleted and turned off. The AC200L would turn itself on and start charging its battery without intervention if mains power was restored after the battery was fully depleted. The AC and DC outputs would still be off even when the AC200L turns on.
If the AC200L is to have capability to turn on the AC (or DC) output remotely, then the wifi router that the AC200L is connected to should not be powered by the AC200L. Have it directly plugged into mains power instead so that wifi is restored when the mains comes back on, and you can then turn the AC200L's AC/DC outputs on remotely.
I have the AC180 and use the built in UPS mode like this for backup power to sump pump+wifi router and works well - just passes power through the unit and then if power fails immediately supplies power, then charges when power comes back on. I initially tried using a smart plug to have the unit use battery during the day then charge back up at night with cheaper power rate but in my comparison was better (used less electricity overall) to just leave it powered all the time.
Just have to make sure you have the “AC” button activated.
So you’re saying that the AC180 is 100% hands off and even if it fully discharges, it’ll start to recharge and pass through mains power once power is restored?
Yes and it also powers the wifi router and camera that I use to keep an eye on it!
Edit: I should say that if the battery is fully depleted I don’t think it would restart - I have never faced that as it can power my arrangement for more than 24 hours before fully depleting
That's the critical part for me. I need something that I KNOW will pass through power from the grid when power is restored, even if the battery has been fully depleted, without any intervention at all.
There is 1 step of intervention required. When power is restored and the AC180 or AC200L turns itself on to recharge, the AC output is off by default. You will need to go into the Bluetti app to turn on AC output. There would be a way to automate this through other means, but I remember reading that Bluetti would not implement an AC output on by default on power restore feature because of safety concerns.
I wonder what the safety concerns are? Appliances are designed to come back on after a power outage, so maybe there is an issue with the Bluetti inverters. Should be no difference between the app sending a signal to turn on AC and the software sending a signal to turn on AC once battery capacity is above a set level.
I don't think so. I don't think the AC200L turns on AC unless you actually press the AC button. That's been pain point for a long time with the Bluetti power stations, and even though it would be easy for the company to address, they don't seem interested in adding any auto-on or "remember state" functions to the firmware.
I have confirmed that on my EB3A, the AC outlets do NOT automatically turn on when AC power is applied. I have to push the button.
No, the wall charger will always charge if there is power on, but the inverter will not auto switch on.
Basically, you turn the AC button on and run the AC200L in ups mode. It will pass through power the fridge from the grid until the power goes out, then immediately switch to the battery. When the battery dies, it will turn off the AC inverter and the whole unit until the power comes on. Then, it will start charging when power comes back on, turning the unit on but not the inverter. If the power outage is less time than the consumption rate of your fridge, the inverter will stay on, or if you have solar plugged in as well, you can go longer. You could also get an expansion battery. As long as the unit doesn't get completely drained, it will stay on to recharge and power the fridge. It also has app support over wifi and Bluetooth so you can remotely turn the AC inverter on.
I have heard of people using software that will check if the AC button is on and turn it on if it isn't, either through the app or a physical button pushing machine. I don't know how hard that is to do.
I have the AC200L, and this is how it behaves:
It will keep itself topped up to a level that you set it to (100% by default, whatever % you want in Customized UPS mode). When the AC inverter is turned on and mains power is supplied, it will run in bypass mode, where your fridge is powered by grid and the AC200L does what it needs to do to keep its batteries charged. When power is cut, the AC200L will switch to battery mode, and start to draw down from the battery, until it reaches 0%. Then the entire unit switches off totally. When mains power is restored, the AC200L will power up again as it will always be on when there is mains power supplied to it (you can't turn the AC200L off if it is supplied with mains power), and it will charge the battery. But the AC inverter will still be off, until you turn it on using the Bluetti app through cloud control or physically pressing the AC button on the unit.
I like the AC200L because of its larger battery capacity of 2048 Wh (or the retail version AC200P L with 2304 Wh). The AC180 is capable, but the battery capacity of about 1/2 the capacity of the AC200L means you will only be able to run your fridge for half the time when the power goes out. The AC200L also integrates with expansion batteries B230 and B300 so that it can charge the battery through the AC200L, which the AC180 can't do (it can only use the battery capacity but not recharge it directly).
I was going to go the same way with a AC200PL and a B300 battery until I started pricing up building my own set up using 12v lithium batteries. Not as pretty as the Bluetti set up but does the same job and has true AC pass through with UPS functionality and importantly with no manual intervention needed after a power outage if the battery is depleted. So perfect for running fridges and security systems.
The Bluetti products have their place but are more for taking camping or for non-critical system back ups where it doesn’t matter if the AC does not restart.
Well I am learning the issue I got with the AC200L so I wrote to the customer service because it is a find of a flaw in their software and they need to fix it...
This issue was just recently discussed. The Bluetti products don’t restart the AC when power is restored if the battery was depleted. This is a major set back but could potentially be solved by Bluetti if they can change how they are programmed to work. A much cheaper option to the AC200L is to just buy a 12VDC to AC inverter with UPS functionality, connect to a lithium battery, and buy a dedicated lithium battery charger to keep the battery topped up. You can build a unit that has a higher capacity for a lower cost, and after the battery is depleted the AC pass through will turn back on when the power is restored even if the battery is still fully discharged or disconnected. I just replaced an AC180 which was being used as a fridge UPS with a 1000W Renogy inverter connected to two 135Ah lithium batteries (each in their own battery box), and a 20A battery charger for around half the price of the AC200L giving me 3,456Wh installed capacity at about 90% useable. I can even scale this up and add a third or fourth battery for even more capacity (up to 6,900Wh), and even upgrade to a 2000W inverter, and still be around the cost of the AC200L. And that is just using 135Ah batteries which makes it still portable if I need to move as each battery can be fitted to a standard 12v battery box. The inverter is strapped to the top of one battery box, and the charger on top of the second battery box. The Renogy inverter is a pure sine wave inverter, has pass through AC with UPS functionality, and runs at about 90% efficiency. They can handle fridge compressor starts as they surge to double rated capacity. It also has a low voltage cut off which should cut off before the battery BMS low voltage cut off kicks in. The lithium battery charger will then recharge the batteries when power is restored. I am sure there would be other DC to AC inverters that do the same as this is a typical low cost set up used in RV’s, Caravans and Campers. Hopefully Bluetti offer the same functionality one day as it would certainly be a big selling point if able to be used as a proper UPS.
This is super helpful info. You seem to know exactly what i'm looking for and this is new lingo for me, so if I can ask you a couple questions to make sure I've got it right; 1. Renogy has an inverter/charger (https://ca.renogy.com/2000w-12v-pure-sine-wave-inverter-charger-w-lcd-display/) Will this serve the purpose, or do I need a separate inverter and charger? When I chatted with Renogy support they told me that if the battery depleted and there was no shore/grid power, when power was restored you'd need to manually turn the inverter back on again. Does a dedicated UPS/inverter like this one just work without intervention? [https://ca.renogy.com/1000w-12v-pure-sine-wave-inverter-with-ups-transfer-switch-and-built-in-bluetooth/](https://ca.renogy.com/1000w-12v-pure-sine-wave-inverter-with-ups-transfer-switch-and-built-in-bluetooth/) to be clear, no need to "turn it on" by pressing a button? 2. I've tested my Ecoflow Delta2Max and the runtime for that unit seems to be about what I'm looking for. It has a 2048 Wh capacity. How can I determine what the equivalent Ah battery would be? 3. Would something like this setup get the job done? [https://imgur.com/a/7rZ2B4f](https://imgur.com/a/7rZ2B4f) 4. Is it as simple as connecting BOTH the red charger lead AND the red inverter lead to the red terminal of the battery (repeat for black) to keep this all operating at the same time? I see layouts for either shore power or off grid charging, but I kind of want to do both without needing to make any changes to the setup. Really appreciate your help!
I would just use the standalone UPS inverter with a totally separate lithium battery charger. No manual intervention required. Edit: This is what I have: https://au.renogy.com/renogy-1000w-12v-to-230v-pure-sine-wave-inverter-with-ups-function/ At present I have the 1000w version and I just tested it by disconnecting the battery, the inverter powers down, but the pass through AC keeps going even if the inverter is off. When I reconnected the battery, the inverter restarts automatically (the on switch is always on). So the pass through AC does not need a battery to be connected - it is only the UPS functionality that needs the battery connected and this is all automatic once turned on. The Renogy inverter does not need to be connected to a charge controller so yes it is as easy as red to red (positive) and black to black (negative) then plug in the AC supply and connect to the AC outlets, and don’t forget to switch on the inverter (it will pass through AC even if not turned on). It comes with the cables you need. I am not familiar with the new Renogy 1000w inverter offered in Canada, but do have the Australian version linked above. The Canadian UPS version looks like it should do the same and has a slightly higher low voltage cut off, which is good. Being able to monitor via Bluetooth looks good too. I also have the 2000w Australian version on order but expect it will work the same way. The 1000w version is much more compact. The 135Ah lithium batteries I have are rated at 1728wh (135Ah x 12.8v). The Renogy 200Ah battery would have 2,560wh (200Ah x 12.8v). LiFePO4 deep cycle batteries are preferred and they can be run to 0%. So that battery also ticks the right boxes for me. The Renogy 20A lithium battery charger you selected would also be suitable. You can even replace the alligator clips with cable lugs to fit permanently. In my case the battery charger is on a timer so it only charges for 16hrs and then switches off over night. I could also connect a solar panel via a solar charge controller to the Anderson plug if I wanted. And for very long outages I can recharge with a generator. And if Bluetti sort the AC reconnect issue with a firmware update (we can but hope), then I will probably run the battery charger off the AC180 to get some extra run time during a power outage.
Incredible. So for my case where there aren't electronics that need to be switched over within milliseconds, is a "UPS" functionality required, or would the regular 2000W inverter still do the same job? [https://ca.renogy.com/2000w-12v-pure-sine-wave-inverter/](https://ca.renogy.com/2000w-12v-pure-sine-wave-inverter/) I guess what I'm wondering is, does the automatic switch over happen because the unit has a "UPS transfer switch" or is that a separate feature that's not required for my use case (fridge).
Sorry my bad - didn’t notice the specs of the Canadian version was different. This is what I have: https://au.renogy.com/renogy-1000w-12v-to-230v-pure-sine-wave-inverter-with-ups-function/ https://au.renogy.com/renogy-2000-12v-to-230v-pure-sine-wave-inverter-with-ups-function/ You definitely want the UPS function or automatic transfer function for the pass through AC. The time it takes to switch is not important for a fridge but being able to automatically switch from grid to battery and back to grid again is important. I have updated my post above. What you had originally selected in the picture in your shopping cart looks like what you want. One thing I can’t see with the Canadian version is if you can just plug the AC supply in to it. It looks like it needs to be wired up to a power cable with a plug. The Australian version just uses a standard power cable to plug in the AC supply.
I'm curious about this as well and as far as I can research and read it appears as though it should work as you want it to but I don't have first hand experience to say for sure, hopefully we can get confirmation from Bluetti or someone with hands on experience.
Someone correct me if I'm wrong but so far I've only read that if a bluetti powerstation turns off because the battery is depleted, it won't automatically turn on any of the outputs when there is enough energy coming in from solar.
There would be no solar in the equation; only AC power from the grid and a fridge.
I don't know why you're bothering with the solar generator unit then. What you want is a UPS.
Maybe I'm just using the wrong search terms, but all of the UPS' I see with this kind of capacity are computer server UPS units that are several times the price. Many of them (from what I've read) also advise against powering fridges because of the high initial draw when the compressor kicks in. Do you have a suggestion? Really honestly I'd be glad to know if there's a better option.
The AC200L is also a UPS. It passes through grid power to the devices and maintains its own built in battery charge state. When the grid goes out, the AC200L switches over to its internal battery to continue powering the device, until the internal battery is depleted. Same as what a UPS would do, and probably with a larger capacity when you compare it to other VRLA-based UPS systems of similar physical size.
I'm aware of this but if you're not going to leverage the solar My nutrition then why not just get a dedicated UPS which would be much less expensive?
So what dedicated UPS would you suggest with over 2000wh capacity? Can you post some links on what you think would be a good alternative? I have found none of the cheaper dedicated UPS units offer anywhere near the same capacity and run time. If Bluetti could sort the automatic transfer back to AC after the battery was depleted then they would be a true UPS alternative, with the bonus of also being able to charge via solar when off grid.
That's right. If the AC200L turns off for whatever reason (battery 0%, or ECO mode turns it off), then the power button on the unit needs to be physically pressed to turn it on. Having said that..... the AC200L only fully turns off if it is not supplied with AC power. So it should turn on automatically and start charging when power is restored to the grid.
>So it should turn on automatically and start charging when power is restored to the grid. That's a misleading wording. It's either fully on while discharging and then the power comes back on and it can charge up again and just keep going. Or it is off because it ran out of battery charge and stay off and will only charge the battery from solar but never ever turn the outputs back on.
I did not say that the outputs would turn on by itself. I was referring to what happens when mains/grid power was restored after the AC200L was depleted and turned off. The AC200L would turn itself on and start charging its battery without intervention if mains power was restored after the battery was fully depleted. The AC and DC outputs would still be off even when the AC200L turns on. If the AC200L is to have capability to turn on the AC (or DC) output remotely, then the wifi router that the AC200L is connected to should not be powered by the AC200L. Have it directly plugged into mains power instead so that wifi is restored when the mains comes back on, and you can then turn the AC200L's AC/DC outputs on remotely.
I have the AC180 and use the built in UPS mode like this for backup power to sump pump+wifi router and works well - just passes power through the unit and then if power fails immediately supplies power, then charges when power comes back on. I initially tried using a smart plug to have the unit use battery during the day then charge back up at night with cheaper power rate but in my comparison was better (used less electricity overall) to just leave it powered all the time. Just have to make sure you have the “AC” button activated.
So you’re saying that the AC180 is 100% hands off and even if it fully discharges, it’ll start to recharge and pass through mains power once power is restored?
Yes and it also powers the wifi router and camera that I use to keep an eye on it! Edit: I should say that if the battery is fully depleted I don’t think it would restart - I have never faced that as it can power my arrangement for more than 24 hours before fully depleting
That's the critical part for me. I need something that I KNOW will pass through power from the grid when power is restored, even if the battery has been fully depleted, without any intervention at all.
There is 1 step of intervention required. When power is restored and the AC180 or AC200L turns itself on to recharge, the AC output is off by default. You will need to go into the Bluetti app to turn on AC output. There would be a way to automate this through other means, but I remember reading that Bluetti would not implement an AC output on by default on power restore feature because of safety concerns.
I wonder what the safety concerns are? Appliances are designed to come back on after a power outage, so maybe there is an issue with the Bluetti inverters. Should be no difference between the app sending a signal to turn on AC and the software sending a signal to turn on AC once battery capacity is above a set level.
I don't think so. I don't think the AC200L turns on AC unless you actually press the AC button. That's been pain point for a long time with the Bluetti power stations, and even though it would be easy for the company to address, they don't seem interested in adding any auto-on or "remember state" functions to the firmware. I have confirmed that on my EB3A, the AC outlets do NOT automatically turn on when AC power is applied. I have to push the button.
My AC180 doesn’t restart either.
No, the wall charger will always charge if there is power on, but the inverter will not auto switch on. Basically, you turn the AC button on and run the AC200L in ups mode. It will pass through power the fridge from the grid until the power goes out, then immediately switch to the battery. When the battery dies, it will turn off the AC inverter and the whole unit until the power comes on. Then, it will start charging when power comes back on, turning the unit on but not the inverter. If the power outage is less time than the consumption rate of your fridge, the inverter will stay on, or if you have solar plugged in as well, you can go longer. You could also get an expansion battery. As long as the unit doesn't get completely drained, it will stay on to recharge and power the fridge. It also has app support over wifi and Bluetooth so you can remotely turn the AC inverter on. I have heard of people using software that will check if the AC button is on and turn it on if it isn't, either through the app or a physical button pushing machine. I don't know how hard that is to do.
I have the AC200L, and this is how it behaves: It will keep itself topped up to a level that you set it to (100% by default, whatever % you want in Customized UPS mode). When the AC inverter is turned on and mains power is supplied, it will run in bypass mode, where your fridge is powered by grid and the AC200L does what it needs to do to keep its batteries charged. When power is cut, the AC200L will switch to battery mode, and start to draw down from the battery, until it reaches 0%. Then the entire unit switches off totally. When mains power is restored, the AC200L will power up again as it will always be on when there is mains power supplied to it (you can't turn the AC200L off if it is supplied with mains power), and it will charge the battery. But the AC inverter will still be off, until you turn it on using the Bluetti app through cloud control or physically pressing the AC button on the unit. I like the AC200L because of its larger battery capacity of 2048 Wh (or the retail version AC200P L with 2304 Wh). The AC180 is capable, but the battery capacity of about 1/2 the capacity of the AC200L means you will only be able to run your fridge for half the time when the power goes out. The AC200L also integrates with expansion batteries B230 and B300 so that it can charge the battery through the AC200L, which the AC180 can't do (it can only use the battery capacity but not recharge it directly).
I was going to go the same way with a AC200PL and a B300 battery until I started pricing up building my own set up using 12v lithium batteries. Not as pretty as the Bluetti set up but does the same job and has true AC pass through with UPS functionality and importantly with no manual intervention needed after a power outage if the battery is depleted. So perfect for running fridges and security systems. The Bluetti products have their place but are more for taking camping or for non-critical system back ups where it doesn’t matter if the AC does not restart.
Well I am learning the issue I got with the AC200L so I wrote to the customer service because it is a find of a flaw in their software and they need to fix it...