CA Traveler wrote:
Serial vs Parallel Thoughts
Using 2x24V panels for 12V charging yields the exact same power input to the controller so I would not expect any difference based on the panels, ie the voltage is not less in the early morning. So twice the voltage or twice the amps. Wiring is different and a given MPPT controller could have different efficiencies depenting on the input voltage or amps.
For 2x12V panels for 12V charging could use a PWM controller for parallel and a MPPT controller for serial which involves wiring and controller differences. It also involves temperature differences and could favor either one. With morning temperatues above or below 77F (STC) as the panel output can favor one or the other. If the same MPPT controller is used for serial vs parallel then likely the same except for wiring and efficiency.
Just my 2 cents. I don’t recall seeing in testing on this subject.
I have seen several tests and such on the benifits of serial over paralell. there actualy will be a difference in morning votage between the two even if using 24V panels. my controler can take 140V in so that would let me stack three 24V panels and still be save. 4 and I am asking for trouble. but lets say I have three and early morning they are putting out 6V each, that adds up to 18V which is over the threshhole to start charging. if I had three paralell then it would only be 6V and wouldn't get a charge untill the sun came up more. not sure if thats what you were getting at but thats how I read it so I apoligize if I misunderstood what you were trying to say.
Steve
