AC300 - Working Mode question

I hope there is a simple answer, but I can’t figure it out. I have AC300 and 4 -B300 batteries (12,288watts), and 2400watts solar panels.

  • Every hour AC output is about 500watts. During the day solar keeps it topped off to 100% till 4pm. - After that, the batteries power the AC output.
  • Around 6am, batteries get down to roughly 45%.

Question: What can I do to bring the battery charge (using GRID power) from 45% up to 75%, then shut off GRID power at 75%. Solar would then kick in around 10am. If its a bad solar day and little PV power, I’d like GRID power to kick back in whenever it gets down to 45%, power back up to 75% (and GRID power off) - Repeat as needed…

Hi @mikechilcott

I think what you are searching is the PV Priority Mode. As the name of this mode say, its feeding the B300 primarly with energy from the PV. You habe the option to set a SoC in the App in this mode.

Im not 100% sure and cant test it right now due a lack of sun but when i remember it correctly, you set the slider to the lowest value where it should use PV instead of grid.

For example, you want that you B300 have at least 10% SoC, then set this value to 10%. Grid will charge the unit to 10% and everything above by PV charge.

If someone know it more precise than me, feel free to add a comment. As for now, i would try it like that :slight_smile:


So I switched over to “PV Priority UPS”, set level to 46%, GRID is still charging. Cloudy day, so PV is still low…
Thoughts? Do I need to unplug the GRID cable, and plug back in for it to take?

Thanks in advance

Switched it over to “Standard UPS” mode, and this is how it is charging…

If I remember right grid will power the AC load until your solar charges the batteries to about 10% above your PV priority setting, then it will go to PV only until the batteries get back down to that setting before grid kicks back on.

Unfortunately don’t think the exact configuration you are describing is possible without either:

[a] constant monitoring and manual intervention;
[b] some sort of automation (e.g. Home Assistant integration).

Speaking from experience (owning 3 AC300s, 2 in split phase, one standalone/spare, with a 7.5kW panel system, and have done the HA integration, but only use it for monitoring, for now, although I’ve tested controlling the AC300s from HA and it works but decided that I wouldn’t need automation after all, at least for now - the main reason being that the spread between my overnight/off-peak and daytime/peak rates is not large enough to justify it).

Without the options above, the best you can do is using a combo of SOC low/high values (45% and 75% in your case) and time slots (daytime/overnight) in Custom UPS mode while leaving the “Charge from Grid” switch “ON”.

It will allow you to have an alpha-floor protection (to use an aviation term) at 45%, i.e. if you drain to 45% the AC300 will go into pass-through mode, during the day, no matter what. Overnight, it will either charge back to 75% (if your actual SOC is somewhere between 45% and 75% when the AC300 switches to off-peak mode) or stays at the current SOC until the morning, in pass-through mode (if you are above 75%). In the morning it will turn grid charging/pass-through off and charge/supply the load from PV, unless there is not enough PV, in which case it will drain to 45% and go into pass-through.

There are many additional, minor nuances in this setup that I would not go into now.
If you feel like experimenting with the above config and have any question, let me know.


Forgot to add:
You may want to check out Jeff Hagen’s superb " Bluetti UPS Modes Explained" video on YT, on his WaveformScience channel.

The Picture with the PV UPS mode on just draw from the grid because the PV income isnt enough to furfill the AC load. It will use PV energy as long as possible and add the rest via grid.

Standard mode charge with full power, because its goal is to keep the AC300 at max SoC.

So what is best for the batteries/system (now day 3 w/o much sun):

  1. Switch to “Standard UPS” mode, using GRID @1.4kw and get batteries up to 99-100%, and switch back to “PV Priority” or
  2. Keep it on “PV Priority” and slowly keep batteries at SOC 46%, till PV starts taking over?

Thanks - Mike