You would be surprised, a east west parallel string the lost is minimal. Voltage is largely the same for east west string through most of the day except near sun rise and sun set. Big difference in voltage is when lost happens. See the link at bottomI unfortunately didn’t catch a similar issue in my design. I had 36 panels installed in July, 18 on main house and 18 on my detached garage.
I have two tesla 7.6 inverters based on my powerwall+ units.
tesla engineering decided to do the following:
2 mppts on main house
10 panels in series facing east
8 panels in series facing west
for detached garage I have 2 mppts with one jumpered similar to the op to effectively make “3 mppts”
8 facing east
8 facing west
2 facing south
However to save on wire they combined the east and west panes into one set of wires to pull through the underground conduits and as mentioned jumpered the mppt at the inverter. I believe this is causing pretty significant system losses in the morning and evening but tesla is turning a blind eye. Unfortunately once the system has been installed tesla just doesn’t care and will ignore the design flaw. In addition to this since day 1 the two panel pane does not produce power and has a ground fault. Still battling for them to fix that.
So from my experience, stand your ground until they design the system as you want it to be. If I would have caught this design failure earlier I would have declined installation until fixed.
Have you try rebooting the inverter for the 2 panels inverter near solar noon? Sometime morning moisture that dry out after a while would work after a restart at noon. At least that may help troubleshoot if it works after a restart at noon.
https://www.fronius.com/~/downloads...ntated_PV_systems_with_one_MPP_Tracker_EN.pdf