question

Hi Folks

I could use some advice! I am pretty new to this...

Suppose I have solar serial strings with 9x450W (48V, 10A) solar panels.

The voltage from my panels is then 432V from each string and therefore remains 432V if I connect two strings in parallel (or a little less in reality due to actual conditions, so the voltage is within range).

But if I combine my two strings in parallel, my current from the two parallel strings is 20A (10A + 10A).

The MPPT 450/100/200 spec sheet says:

Maximum PV array size per tracker 7200 Wp (450 V x 20 A)
Max. PV operational input current 18 A per tracker
Max. PV short circuit current 20 A per tracker.

The MPPT 450/100 has a PV input limit of 18A per tracker and it has 2 tracker inputs.
The MPPT 450/200 has a PV input limit of 18A per tracker and it has 4 tracker inputs.

A single 18A tracker port then can't handle the 20A (10A + 10A) if I want to include two PV strings (as described above) in a parallel connection, right?

I have seen debates on the internet where some people say the tracker port will regulate the 20A to 18A as needed, and other people say 20A input will fry the tracker input MOSFETs.

Can anyone help me out with this?

I can put each of the two strings on its own PV tracker connector (10A each so it's below 18A), but then I can not expand in the future with more strings into the MPPT 450/100's 18A connectors. So if I want to leave space for expansion with future strings, I would need to get an MPPT 450/200, which has four tracker inputs of 18A each, then can I possibly add 2 more strings in the future, but the 450/200 costs quite a bit more than the 450/100.....

Any help would be very much appreciated!

Regards and thank you!