I gave the batteries about 15 hours of charging. The entire setup was stable at 54.0V, but each "pack" was quite different. (Yes they should be balanced, no I'm not going to, for now)
When I switched over to the packs the heater ran for about 15 minutes, I turned on the refrigerator, the deep freeze, the water cooler (all 4 have induction motors), 23 lights, a big TV and sound system, and a big computer, plus all the wifi stuff.
After running the entire house off the batteries, they are at 52.9V.
I'm not sure what you call my system. A/C or D/C coupled, but it works great.
In grid-tied mode, my inverters are just chargers for the batteries.
In off-grid mode, my inverters run the entire house from the batteries.
To change from grid-tied to off-grid;
#1 Turn OFF the load's panel from the grid, at the main switch to the panel.
#2 Switch the giant orange knife switch from Source to Supply.
#3 Turn ON the inverters.
This is a manual operation, and yes there is a chance it can be done completely wrong, ie supply the output from the grid!
It is possible to through the knife switch with everything on. If done a few times it is just going to weld itself in place finally. Turn that stuff off before switching anything!
Emporia Vue loads panel monitor doesn't quite know how to handle a panel with TWO Sources.