I am busy looking into doing a solar install, might start out small and grow the system. I currently have 4 x 450w panels, East facing,  running on a micro-inverter. What i was thinking of doing is adding another 4x 450w panels to this East facing setup and then connect these to the new inverter, then adding maybe 4 x 545w panels west facing for now. I am thinking of either a 5kw or if funds allow 8kw SunSynk inverter. 

Questions.

1) Is it okay to have unbalanced mppt's, so mppt 1 will have a max of 3600w and mppt 2 will have 2180w.

2) If I go for the 5kw is the 545w panels okay for the mppt?

 

Reason for this setup is I also have 4 x 330w panels on another 1.2kw micro inverter, which I was thinking of connecting to the AUX port of the SunSynk. These would face almost North but I am limited to 4 panels facing North due to roof space. So maybe down the line I could add more panels to the West facing mppt if I need more afternoon power.

What I am worried about if say 1 year or so down the line I am looking for 450w panels and you can't get them, so was thinking of rather going for the 545w and hope they are around.

Hi all of that won't harm the inverter. 50volts times 4 is only 200volts way below the limit.