question

harrys avatar image
harrys asked

SmartSolar selection for 6 x 30Wp panels

Hello, new to this forum.

I'm planing a solar system for our caravan currently. We try to maximize power on a small and pretty cluttered roof. The best I could achieve so far is using 6 panels (including a bypass diode each) with 30Wp each.

Entering this into Victron's configuration tool results in two recommendations depending on whether we connect the 6 in series or have 2 parallel series with 3 each:

  • 6 panels in series: MPPT 250/60
  • 2 series with 3 panels each connected in parallel: MPPT 100/15

The first one looks heavily over dimensioned and is too expensive for the purpose.

For the second one I see a major disadvantage: these 6 panels will have slightly different orientation and very different shadowing situations (antenna, AC). So using a parallel connection seems like a chaotic solution with unexpected results.

For a home solar solution I'd go for an inverter with two strings / MPPT, but this isn't a solution with Victron products to my understanding. Instead, the solution could be using two MPPT 100/15 in parallel?

Questions: pros/cons for each of the solutions beyond the above findings? Other options? For the last approach: do two SmartSolar chargers work fine in parallel and are they synchronized somehow? I saw older discussions on the later from 2019. At this point a sync feature has been planned...

Thanks for your thoughts.

MPPT SmartSolar
3 comments
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Alexandra avatar image Alexandra ♦ commented ·

@HarryS

And there is also the 75/15 as well.

Depends on the VOC....

6x 30W panels is only 180w on a 12v system that is 15Amps of charge. Or did you mean to say 300W panels?

You are probably better if with pwm chargers if you are splitting them up.

0 Likes 0 ·
harrys avatar image harrys Alexandra ♦ commented ·

The config tool calculated a 100|15 for a single 3x30 string too. But you are right - looking at the specs, two 75|15 should be fine too (VOC in range). The overall dimension is 6 x 30Wp, so 180Wp overall.

0 Likes 0 ·
kevgermany avatar image kevgermany ♦♦ harrys commented ·
Did you also take temperature compensation into account?
0 Likes 0 ·
0 Answers