60 Cell Panel vs 24v Bank MPPT and PWM UPDATE
UPDATE--results with MPPT posted 1 June. Got a chance to run this test today with no clouds but a slight haze up high so not quite 1000 insolation, showed as 8.93Isc vs rated 9.0, however that did ...
Forum Discussion
Salvo wrote:
How do you know the controller is in mppt mode and not pwm? In pwm mode the controller has at least 1V drop.
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Easy, it is only in MPPT during Bulk and it said it was in Bulk and rated Vmp is 30.2 and it was doing around that going from 29 to 31 during the run.
As soon as it went to Float (and so into PWM with no MPPT) that jumped to 35v, which was what I was getting before the test began, when it was in 12v configuration and in Float as the "panel voltage" that I took then at 34.1v (rated Voc is 37.4 but you get lower Voc with low light and high temps. In this case it was poor insolation causing the low voltage.
I see on the IV curves that 5 amps I saw goes with about 600. (9 amps goes with 1000) Seems about right with all that overcasting cloud the sun was trying to work through at the time. ( It is worse now, supposed to rain tonight, so I just got that test done in time :) )
