BFL13 wrote:
Mr Wiz is right about the 50 cent part of course. I do have an 'attitude problem' wrt MPPT.
I am still hoping to run a comparison test this summer with my set up, (just switching controllers in place and see what happens) and report how that goes. The guy says he plans to let me try one out when he has one loose later on, since he is interested in how that turns out too. Fingers crossed.
I was getting 8.5A max, usually about 8A from my panels (160W) with the 3 stage PWM controller. Right near the max rated panel output of 9A. Note that with panels with output voltage near 20V or so, you can't get max power (watts) with a PWM controller, your limited to the panels output current, so 9A x 13V=120W.
With the morningstar MPPT controller I see as much as 12A on a discharged battery and regularly see 10A even as the batteries get near 90% SOC. So, yes the MPPT controllers can give more current, but certainly at a cost. Plus mine is programmable so I have reprogrammed it to suit my charging needs.
Is it worth the extra $200??? that's for each of us to decide based on our use case.
And yes, the MPPT controller is more complex than PWM. It's a switching power supply (DC-DC converter) with variable output voltage control.
