Charging Dual AC500 Split Phase?

My Dad’s home is off-grid. A 14Kw sine wave generator is wired into the home breaker panel. There are 240v and 120v circuits.

We have two AC500 and four B300S with plans to integrate them in split phase mode. The “AC500 Power Suite” is on order. We’ll be hiring an electrician to handle the installation for us.

My question is - What charging setup should I request of the electrician given the AC500’s needs? Do I want one 50A 120v outlet per AC500? Something else? I’m finding documentation on our particular setup almost nonexistent.

Your electrician must wire a 240 VAC 50 A outlet for the AC500 units. Each AC500 must be connected to one of the two phases, and the special Communications cable must be connected to both AC500 units. Finally follow the user manual steps to setup the Split Phase operation so one AC500 is Master and the othrr is Slave. Use only the Master to turn and off the AC output at its screen or on tbe Bluetti app.

1 Like

Are you saying we would charge both AC500 from one 240 VAC 50 A outlet (NEMA 14-50)? That would require a splitter of some kind correct? Why not have the electrician provide two 120 VAC outlets for charging instead?

One two-pole 50 A breaker can protect both AC300 units, but each unit has to be powered by a separate phase each. BLUETTI does sell the special charging cable, but if you can wire the two original 120 VAC cables that came with the AC300 into a single 240 VAC plug, it can be better. Your electrician should understand. I know because I am an EE with 38 years of experience.

1 Like

AC500 Review and Comparison to the AC300

Go to this thread. Already discussed for what you are asking.

120 is fine as long as you have each unit on a different breaker and and each breaker on a different leg in the panel, usually an even breaker and an odd breaker. I have 2 AC500 in split phase and both individually charging of AC wall outlets.


Could you be kind enough to show a schematic and photos of connections so we all might learn something! Thanks!:grin::wink:

I’m away on vacation at the moment but I will try to explain in more detail.

I set up the AC500 units identical to the split phase video and illustration by Bluetti. They are very strait forward.

The confusing part for me was charging using the two single charge cords supplied with each AC500 unit while in split phase mode, I kept getting alarms and errors. Rather than buying the split phase charge cord from Bluetti, I spoke to an electrician and he explained to me what needed to be done to get the individual charge cords to work.

I will start by saying I’m not an electrician and my explanations demonstrate that fact.

I selected two 15amp outlets in my garage that were on separate breakers. You can check this by putting one prong of your meter in the smaller hole of one outlet and the other in the smaller hole of the second outlet. Make sure your meter is set to proper voltage. Use extension cords if the outlets are far apart. If the meter reads around 240v they are on separate breakers, if the meter reads zero they are on the same breaker.

The next requirement is the two breakers need to be on different legs of the panel, typically even breakers are on one leg and odd breakers are on the other. I had to move one of my breakers in order to have one AC500 on an even breaker and the other in an odd breaker. Of course, if you’re working in a panel you need to be extremely careful or have a qualified electrician do the work for you.

I hope this simplistic overview is of some help. I will send photos when I return if you need me to. Take care and good luck.

:+1:t3: Thanks! Yes I understand - pics are always a good way of explaining w/o explaining!:wink::grin: Safe travels!

Are you able to simultaneously charge and output power with this setup? I haven’t been able to get it to work.

I’m having a hard time trying to respond to your inquiry. I think it’s working now.

Yes, I am able to charge and use energy simultaneously. It took me some time to understand how to set it up but it works flawlessly. You must have a separate breaker for each ac500 and each breaker must be on a separate leg in the panel. Usually the odd breakers are on one leg of the panel and even breakers are on the other. One AC500 is charging from an outlet on an even breaker and the other AC500 is charging from the outlet on an odd breaker. Let me know if you need more information or clarification and I would be happy to help. It’s important each outlet is dedicated to each AC500 or you will trip the breaker.


With the help of an electrician the system is 100% up and running.

To power the house there is an RV style auto transfer switch. With the generator running, it has priority and powers the house. When the generator turns off, the AC500’s in split-phase mode take over (assuming they are already powered on and AC output is enabled). It’s fully capable of running the 240V well pump, the washing machine, etc.

For charging off the generator, there is a 50A 240V outlet that both AC500 are connected to. They each charge quickly at 25A (~3,000 W).

While the generator can be turned on conveniently with a light switch, the AC500’s are in the basement and are not easily accessed. As power isn’t needed all the time, it’s common for the generator and AC500’s to be powered off. Lucky we found that if the AC500’s have charging current, they wake up automatically. So, to wake up the battery system we’ve found we can turn on the generator for 15 seconds, then use the Bluetti app to enable AC output via Bluetooth.