Can somebody QC this series/parallel/charge controller string plan?


Solar Enthusiast
Feb 20, 2021
I cross posted this from my thread in the off grid forum since it is probably more applicable here. Please remove and apologies in advance if that isn't allowed.

Can somebody let me know if I'm thinking about this correctly. The image below shows my winter roof string plan. For now I'm planning on each panel being a Renogy 100 watt panel (21.6 VOC and 5.29 amps). Once I understand panel wiring and charge controllers I may very well change up the solar panel used, but for planning at this point I'm going to assume this kind of panel.

EDIT: Thanks to Forbisher I've updated the numbers to include the VOC and the temperature correction of 1.23 for my location:

Series of 1A, 1B, 1C wired in parallel with Series of 1D, 1E, 1F = 80 volts/11 amps (880 watts which = 74 amps available to charge a 12V system) and therefore should be tied into a Victron SmartSolar 150/70

Series of 2A, 2B, 2C wired in parallel with Series of 2D, 2E, 2F = 80 volts/11 amps and likewise should be tied into a Victron SmartSolar 150/70

Series of 3A, 3B, 3C, 3D wired in parallel with Series of 3E, 3F, 3G, 3H = 107 volts/11 amps (1177 watts and thus 99 amps available for charging) and therefore tied into a Victron SmartSolar 250/100

Panels 4A, 4B, 4C, 4D, 4E, 4F, 4G wired in parallel = 186 volts/11 amps (82 amps for charging) and that will tie into a Victron SmartSolar 250/100.

Panels 5A, 5B, 5C, 5D, 5E, and 5F = 160V and 71 amps for charging and thus also a Victron SmartSolar 250/100

5 different SmartSolar charge controllers for the winter roof. Not sure if they will talk to each other in order to charge the battery bank efficiently though, haven't done enough research. Am I on the right track?

The Victron Smart Controllers (recommended by Relion) I'm looking at are from here:

Many thanks for any feedback on what I'm no doubt missing when it comes to wiring panels into charge controllers.


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