Any electricians in the house?
Wow. I have never seen a solar array with an AC output. You have to have an inverter to get that. It also sounds like you want to parallel both the solar array and the standby generator. I am no expert in this but this is what I see your system looking like. I agree with what has been said, you need a consultant to help you out. I am confident that you will end up separating some of your loads out of your panels. Supporting 400 amps is going to be a challenge in a residential application. Anyhoo, this is what I THINK you are saying.