Solar Panels - Series or parallel?

[Stemar]

I have a pair of panels, 100W each, IIRC, but I've lost the paperwork, and they don't seem to be available any more. They were mounted under the boom, so were wired in parallel. I'm moving them to a frame above the davits, so they shouldn't be shaded, and I'm considering adding another similar, but not identical pair, all fed into an MPPT controller.

Plan A is to wire each pair in series, and the pairs in parallel. Does this sound reasonable?

 

[Refueler]

Isn't the answer in the potential total voltage of each pair - deciding series or parallel ? can the controller accept such voltage ?

 

[lustyd]

They should have a label on the back with details of voltage etc.
you probably want a second mppt for best performance.

 

[jakew009]

Generally speaking you are better putting identical panels in series up to the limit of your MPPT, unless they are likely to be shaded.

If they are not identical, better putting them in parallel, but they need to be similar vmpp or its better to put them on a second mppt.

 

[tillergirl]

I have a pair of panels in series. The only recommendation was to match the pair, jakew009 is right. Parallel if not identical. The purpose for me is to have 24v.

 

[Baggywrinkle]

Quick explanation of the maths.

Om top of this, modern half-cut solar cells combined with MPPT solar controllers improve partial shading performance further by dividing modules into two independent, parallel-connected, top-and-bottom halves.