Charge Priority Modes - Grid Tie PV Backup

With the new AC300 and AC200Max units, Bluetti is stepping up from portable power backs into potential home backup and off-grid applications. Typical PV setup has Grid Tie inverter that cuts out when the grid is out, depriving the home from power when power is most valuable. One can connect some of their PV panels in parallel to their AC300 / AC200Max for it to become their backup power source when the grid is out and their main grid tie inverter shuts down. However, this won’t work normally as the two MPPT would be fighting one another. One can wire up HV DC relays such that the PV lines are only connected to the AC300 / AC200Max when grid is out but that is quite complicated.

If AC300/200Max can implement charger priority modes then this can solve that problem. If set to AC priority mode, the AC300/200Max would effectively disconnect and not charge from the PV inputs, thus allowing it to remain connected in parallel to the main grid tie inverter. When the grid is out, the AC input to the AC300/200Max is out and then the PV charging would turn on.

There can be other modes such as PV priority which would utilize renewable energy whenever it exceeds a certain value before using AC.

Some of the larger hybrid inverters have these features. At this point the AC300/200Max has enough capability to take advantage of these. Something to consider. \