I don't have the Growatts 5000 yet, saving up money, but I'm using the MTTP 20424kv controller/inverter. But this controller/inverter will not handle 220vac air conditioner and heavy usage appliances like my microwave.
So what I did was to make a transfer box with the tree main wires from the utility company (red, black, white) as the input. Then attached the two-wire from my air conditioner to the red and black terminals in my transfer box as to have 220vac for the A/C. Then I ran the black and white (neutral) and the green (ground) wires to the controller/inverter.
In my house sub-panel, I removed the common return bar (common to all-white wires) and moved all appliances to the right side of the panel and everything else to the left side of the sub-panel). Note that I verified that after removing the common crossbar, that there was no continuity between them with no power going to the panel.
Then from my transfer box, I ran the red and white wire from the transfer box to the right side of my panel as to have Utility power 24/7 to the appliances. Then I ran the black and white wires from the controller/inverter (2424v) to the left side of my sub-panel that powers the rest of the house on Solar. - this has been working fine all summer.
I have also installed a set of switches that I can configure in case the Utility power is out for an extended period of time that I can switch to a gas generator as the ac input to the controller. And in case the controller/inverter craps out, I can configure my three switches so the 110vac that would go to the controller will now go to the left side of my sub-panel. So in theory, I have all bases covered for any power issues to the house.
Note this is still an off-grid setup as I'm not feeding power back to the utility company.
The transfer box and the switches are the keys to this system setup.|
With the Growatts 5000, I will be able to reconfigure my sub-panel back to its original configuration. And with the auto-transfer, I will be able to the whole house including appliances. And then taping off the 220/240vac (voltage across the auto-transfer ends) run wires to the A/C.
and if I ever sell this house and the new owners don't want the Solar, just give me 15 minutes and I can the utility re-connected to the Sub-panel and I will tear down the solar system, including the arrays, and take it with me.