2 EP500Pro PV and AC Charging

I just bought two EP500Pro units to act as a home backup system. I currently have a 30A outlet in the garage that I can hook up my gas generator. My goal is use both units in a UPS mode in the event the power goes out. I do have two 200W solar panels on order and my gas generator for an extended outage. I assume you can just charge the units via AC as normal. For the solar, 1:1 panel relationship or is there a way to combine and charge both. Later on I would like to tie a roof solar panel into this. Thank you.