Will my batteries charge from the grid when solar ceases

[alawson1]

I want to build a off-grid solar system to power two 220v mini-splits 24/7, one 24K BTU and one 9K BTU. These are high quality Fujitsu Halycon 22 SEER systems working very well. I am in Maine. With current price of power I am spending about avg. $165/mo. to heat/cool year-round. When both running they are using a combined 660 watts. That will vary of course. My question is not so much sizing the system as I can figure that out and if I figure too low I can add more panels and batteries later but will a EG4, Sol Ark or similar inverter switch over to grid power to charge the battery bank at say 3 in the morning if they are running low to power both systems? I know I will probably need at least 5, 5.12kWh batteries or more to go all night with no autonomy figured in yet. I do not want to sell power back to the grid. I just want to be able for the inverter to sense battery storage is running low and charge from the grid to the units do not shut down before sunshine. I have a back-up generator but don't necessarily want the inverter to start and use that diesel unit.
Is what I want to do feasible? I woould appreciate someones insight. Best,

 

[#40Fan]

Yes. Most off-grid inverters have a line in connection that will allow you to charge batteries when a low state of charge is reached.