12v MPPT and 24v MPPT vs 24v PWM Test
Got a chance to try out comparing amps to the battery using MPPT vs PWM on a 24v battery bank and comparing those with the usual MPPT on 12v with my 230w panel. The bank is four 6s, so it was easy ...
Forum Discussion
CA Traveler wrote:
Home experiments with solar including mine are interesting and generate comments. But repeatable, accurate, etc? Always be suspicious...
My 250W panels are Vmp 30.6V which might suggest that they would not be the best in parallel for a 24V battery. For reference that would be a 12V equivalent of 15.3V. Electrical losses could quickly dilute their effectiveness.
....snipped some................
Flame suit on...
Interesting point.
A 36 cell 12v panel has no trouble charging 12v batteries. The old 32 cell panels did, which is why they went to 36 and now can get batteries into the 14s and even 15s.
My 230w panel has 60 cells and its Voc is 37. I have not tested to higher voltages in "24v" mode where I suppose the batteries would like to see twice 14.6v (29.2)
Have to try that! I see they make 72 cell panels, so maybe that is why, don't know.
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My OP test results are repeatable and IMO "internally consistent" for the amps/volts/watts so there doesn't seem to anything "wrong" AFAIK. It is what it is! (Unless folks on here can point out some errors---in which case I will adjust and see what the numbers look like then)
