mppt or pwm An opinion from Victron
Hi all, Victron, which makes high quality equipment, has charge controllers. At the end of an overview they give their description of the differences between PWM and MPPT. They do not support it wi...
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Sort of what I have been seeing as previously posted a few times.
However, the paper calls "performance" by the watts. This is bogus. Performance is in amps to the battery. Watts mean nothing to the battery. Amps charge the battery.
So it is disguised how the PWM is "under-performing" in watts but doing just fine in amps to the battery.
The other thing is that STC is 25C CELL temperature, not ambient. At 16C ambient, open back panel propped up, under the panel aiming the IR gun up at the white backing a foot away, I got 44C. At 25C ambient, I got 51C under the panel.
Ambient would have to be near freezing to get panel at only 25C.
So it is not made clear that most of your camping time is when ambient is between say 15C and 25C when panel temps are so high that PWM is nearly as good in watts as MPPT, and according to my results at 25C ambient/51C panel --ie, all summer! I got more amps to the battery with PWM than MPPT. This is hidden in that paper by only talking about watts. :(
To repeat my 230w results for comparison I got:
Ambient T, Cell T, MPPT Amps, PWM amps
16C, 44C, 15.5, 14.5
25C, 51C, 13.5, 14.5
However, the paper calls "performance" by the watts. This is bogus. Performance is in amps to the battery. Watts mean nothing to the battery. Amps charge the battery.
So it is disguised how the PWM is "under-performing" in watts but doing just fine in amps to the battery.
The other thing is that STC is 25C CELL temperature, not ambient. At 16C ambient, open back panel propped up, under the panel aiming the IR gun up at the white backing a foot away, I got 44C. At 25C ambient, I got 51C under the panel.
Ambient would have to be near freezing to get panel at only 25C.
So it is not made clear that most of your camping time is when ambient is between say 15C and 25C when panel temps are so high that PWM is nearly as good in watts as MPPT, and according to my results at 25C ambient/51C panel --ie, all summer! I got more amps to the battery with PWM than MPPT. This is hidden in that paper by only talking about watts. :(
To repeat my 230w results for comparison I got:
Ambient T, Cell T, MPPT Amps, PWM amps
16C, 44C, 15.5, 14.5
25C, 51C, 13.5, 14.5
