Existing Enphase system on house, adding 2nd system on barn

[CortexConstruction]

I have 7200W all Enphase microinverters on house with IQ3 Combiner. I am working on adding 4000W of panels with Grid tied inverter to my new barn build and its a 60 foot run to meter and combiner on main house.

AC Wire between house and barn will be 6/3UF will be omni directional meaning when sun up and we are drawing no amps at barn I show max amps going to house at 33. When sun down my max demand calculation at barn about 33 amps coming from house. When generation is equal to demand there will be no load on the 6/3 UF wire to house in my understanding.

Current flow of generation goes- Combiner-Solar Disconnect- Smart meter.

If I add 2nd system with power going 2 ways do I bring to sub panel and then feed into solar disconnect? I am hiring master electrician to do final connections but I am installing solar to grid tied inverter and trenching main 6/3 AC wire between barn/grid tied inverter and grid/smart meter locations.

 

[Lawrence_SoCal]

I have 7200W all Enphase microinverters on house with IQ3 Combiner. I am working on adding 4000W of panels with Grid tied inverter to my new barn build and its a 60 foot run to meter and combiner on main house.

What type of panels? DC or AC coupled? I'm guessing DC-coupled? if yes to DC.. why?
You mention trenching new wire between barn and meter. Is the meter at your house, or at the street? and wif running new wire... and you went AC-coupled (ex. more Enphase), you could run those into the existing IQ3 Combiner (up to 80A?)?
I suspect 9 or 10 new panels, with micro-inverter, wired into existing Combiner, may be cheaper??? but maybe there is more the situation?

How is barn wired now? ie - what is existing wire to barn? number of circuits, etc...? is there a sub-panel in barn already? is trenching from house/IQ Combiner 3 to barn viable?