Solar Controllers--Don't be a Sucker! :(
Just got to say it again, how it is we are sitting here for five months off grid on solar with no problems at all (third season on solar like this), using the non-programmable, non-MPPT, solar control...
Forum Discussion
There is no benefit wiring panels in series. PV cells act just like a diodes. Each PV cell generates about 0.6V. Have you looked at a diode I-V characteristic curve? As V increases, I remains virtually at zero until diode voltage is around 0.4 V. Then current starts taking off.
A closer look at the I-V curve will tell us that with every 0.1V increase in voltage, current increases by a factor of 10.
That means if the solar panel produces a Imp = 10A at 0.6V per cell, it will produce 1A at 0.5V and 0.1A at 0.4V.
You were thinking that adding 2 panels in series will increases voltage to something the controller can work with, but solar current is drastically reduced by a factor of 100 when cell voltage is only reduced by 0.2V.
There is no advantage in series panels.
Sal the mythbuster
A closer look at the I-V curve will tell us that with every 0.1V increase in voltage, current increases by a factor of 10.
That means if the solar panel produces a Imp = 10A at 0.6V per cell, it will produce 1A at 0.5V and 0.1A at 0.4V.
You were thinking that adding 2 panels in series will increases voltage to something the controller can work with, but solar current is drastically reduced by a factor of 100 when cell voltage is only reduced by 0.2V.
There is no advantage in series panels.
Sal the mythbuster
msiminoff wrote:Sounds like some think that mppt excels during dawn and dusk.
This has nothing to do with Maximum Power Point Tracking... It simply a free benefit of wiring panels in series vs. parallel (assuming you don't have to buy a new controller to do so).
