Please may someone clarify something for me on sizing charge controllers:
They are identified as, for eg, 150/100 12/24/36/48.
150 is panel VOC max, 100 is Amps and the rest are the system voltage.
I have been taught 2 conflicting sizing methods:
The number of panels max useable is:
a) based on Amps/(n strings x Isc) i.e. 3 x 265Wp panels per string at 9.03A = 11 strings or 33 panels or 8745Wp (but the MPPT sizing calculator does not offer this answer)
b) based on system voltage x Amps i.e. 48Volt system x 100 = 4800Wp at 3 per string (based on VoC max) = 18 panels maximum. (but the MPPT sizing calculator says we can have 24, or 6360Wp)
Or a 24Volt system = 9 panels maximum, for the same charge controller.
Seeing as the MPPT calculator gives neither answer, then how am I going wrong, or is the calculator wrong?