I haven't bought the ATS yet, so the switch specifics are TBD. But if memory serves me correctly, there's digital ones that have programmable time delays, so I could customize it. If I build in a 5 minute time delay, it should avoid the ride through right?
Since the SE is on AC1 and the grid is on AC2, if SE gets pulled by ATS2; won't the SI still maintain the microgrid off the batteries? If so, wouldn't it still try to sync with the grid?
As I type that I guess you could mean slamming the SE out of phase back onto the grid. But if there's a time delay on ATS2, then it should force a reboot of the SE which would re-initialize according to the grid phase right?
Unfortunately I don't think re-arranging is an option. That would take quite a bit of trenching, rewiring, and permit/inspection work as the systems were installed by different companies and considered two different "plants" by my utility company. Everything from their respective meters back would have to stay the same if I didn't want to get re-approval from the state and utility company. Anything after the meters is just the local construction office and much faster and easier.
From the meter, there's a line tap that uses 4/0 (200A) wiring to my main panel and a separate 4/0 (200A) wiring to the manual disconnect/SE. The grid line itself is capable of supporting a 400A panel (320A continuous) but I haven't looked at what wiring it uses.
You're exactly right. I considered just feeding the main panel since I don't need the extra circuits. But then I got concerned with overloading and surging the main panel if I fed the entirety of the SE into it. The SB/SI system isn't a lot and as you stated is using a 70A backfeed. I'm not sure the SE on 150A would pass inspection if I fed it to the bottom of the panel.
Do you mean like this?
View attachment 19519
It could technically work. According to the SMA manual I can't mix the SI-6048, SI-4548, and SI-5048 in a double split phase configuration. So I would have to put the entire system on SI-5048; which 41.7A of output which is 166.8A continuous; and I'd be able to hold 216A for 30 minutes.
I'd have to pay the utility to do a disconnect to install the ATS, but I could sell the SI-6048 and SI-4058 to recoup the cost.
Just two potential concerns.
1) I'd still be feeding all of solar edge through the main panel in this case and still have overloading concerns. I'd probably need to upgrade the main panel to a 320A panel.
2) Doesn't this assume the SB and SE communicate with the same scale back frequencies and react the same way? I'm not sure if they do or don't so it might not be an actual concern.