I am replacing a growatt inverter with a new EG4 18kpw inverter. On the growatt there was only one spot for ac and it provided ac in and ac out, the EG4 has a grid and line. My question is EG4 keeps saying that the grid needs to be between my meter and my Main breaker. But my system is installed on a detached garage where i back feed a breaker there that back feeds my main breaker panel. can i pull the grid and back feed the system from my sub panel? I am assuming i will only lose the ability to have power in the case of a power outage which i am fine with right now.