Does having a East & South array affect my Grid Inverters efficiency?

[bcroe]

Several equal voltage strings can be tied in parallel, because sun or shade does not effect the MPPT
voltage a lot. The string(s) in good sun will dominate the operation, the shaded string(s) will make a
small contribution with no extra control.

Getting an inverter with multiple MPPT inputs will allow operation of non parallel, different voltage
strings. Bruce Roe

[KenInNC]

Thank you Bruce. I think at the mean time I will keep it simple and do three strings of 7 each. This should give me three strings at 297.5v + -. Two strings should produce well and the East one is better than none.... BUT how do you calculate amperage in a series of seven PVs if each PV is rated at 8amps? I am trying to purchase a DC combiner box and I found one (albeit expensive $300) that is made for three strings and has a arc fault detector and turn off switch which will turn off the DC coming in and I believe the AC going to the grid but I need to look at the schematics a little better. I thought it a bit odd that the DC in and out was 10-6 AWG and the AC out wire size was 16-10 AWG. I see that the maximum input fuse rating is 20A, DC Maximum continuous DC Current is 40A yet the AC Maximum Current is only 24A. I have always used a simple 120v watts to amps idea that for each 100 watts it was 1 amp. So a hair dryer at 1500w would need a 15A circuit. Yet if the AC maximum current is 24A then that seems like I would only be sending 2400w back .. or maybe that per leg which is only 4800w combined. Am I really wrong here? Maybe this box isn't correct for my hopeful 8kw grid tie. Between this combiner box and a AC disconnect (and PV wires) I think I am almost done with the planning.

[KenInNC]

If there is a better 3-4 combiner cut off box out there for under $300 please advise. I did like the fact that the one I found had some grid power down fail safes. I hope to get this up and going before the cold and wet season gets to full time here near the coast of NC. For ease of wiring and access I will be putting the Grid Tie inverter, AC disconnect and the DC disconnect combiner box outside by the power meter for ease of visibility to any fire or emergency responder. Thank you for your advice and help