Use of Outback Inverter's automatic transfer switch

Cuteajax

I have a battery-based solar system with Outback VFX3024E inverter and Midnite classic 200 charge controller at it's heart. I want to implement an automatical transfer switching between the grid and my solar set up based on battery voltage such that I can run my house from the batteries during the day (while the solar array charges my batteries at the same time) and also run on batteries at night until the batteries' voltage drops to a level (user-determined), by which time I want to switch to the grid to run the house and charge my batteries. I know I need an automatic transfer switch (ATS). I read that the Outback VFX3024E has an automatic transfer switch. Can it be used for this purpose or would I need a separate ATS to actualise my needs? I'm I missing the definition of the inverter's inbuilt automatic transfer switch? If yes, what's it's job then?