question

durovenia avatar image
durovenia asked

Combining different size solar panels on camper

Hi all!

I currently have 2x 175W solar panels from Victron on the roof of my camper (Vmpp = 19.4, Impp = 9.03, Voc = 23.7, Isc = 9.89). I have them in series connected to a 100|30 MPPT from Victron. I have limited space on my roof but would like to extend my grid with one or two 55W panels (Vmpp = 18.8, Impp = 2.94, Voc = 22.9, Isc = 3.22). What would be the best way to connect them to my grid?

I understood that It is not advised to mix different panels - especially in series (high-efficiency loss), but parallel should work (with only a slight loss), right? Or am I missing something? Could you help me sort out the right method in case of:

  1. 2x 175W + 1x 55W
    Can I put all the panels in parallel and still run the same MPPT controller, or do I need to put the single 55W panel on its own controller. If so, which one should I go with (hopefully able to use with the same app).
  2. 2x 175W + 2x 55W
    Should I parallel them all or serie-parallel (175Ws and 55Ws separated) and run them on the same MPPT controller, or do I need to run both sets from their own controller? If so, which one should I go with (hopefully able to use with the same app).

I highly appreciate your help.

Cheers,

Joy

MPPT ControllersSolar Panelsmart solar set-up helpsolar sizingBlueSolar PWM
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

1 Answer
hjohnson avatar image
hjohnson answered ·

If I was you, I'd just add another MPPT. The 75/15 is cheap enough, and the 75/10 even cheaper. That will work much better. Just get the SmartSolar and you should be good to go.

2 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

durovenia avatar image durovenia commented ·

This will only work with two extra 55W panels in serie right? Can imagine that only one will not supply enough voltage to get the MPPT running properly. Or will this not be a problem?

0 Likes 0 ·
kevgermany avatar image kevgermany ♦♦ durovenia commented ·

Depends on the panel. Check the specs of the panel. You need actual battery voltage +5V from the panel for the charger to start. So on a 12V battery system you need a panel setup that generates at least 18V, preferably 19 or more. The one you mentioned above will work series or parallel. But I'd wire 2 in series.

0 Likes 0 ·

Related Resources

Additional resources still need to be added for this topic

MPPT Product Page

MPPT Error codes

MPPT 150/60 up to 250/70 Manual