Solar-Panel to Controller Loss
Much has been made of the lower losses on the panel to controller path with MPPT because the amps are less. So once you have your loss measured, how valuable is it to improve on that if you don't lik...
Forum Discussion
Phil, I already did that with my 230w panel (now replaced with the 255w) Posted on 7 May
12v MPPT- 12.7v/14.97a (190w)
24v MPPT- 25.6v/7.95a (203w)
24v PWM-- 25.5v 7.99a (204w)
Same equality for the two 24s as this test, but this time I didn't do the 24-12 MPPT.
I want to compare them all at 50C instead of at 44C to see if it would be worth the trouble to go 24v and PWM. So far it looks like going 24v is the point and it makes no diff PWM or MPPT.
This all started when Mr Wiz had to go PWM as his spare controller when his MPPT died on him. He has a 12v array so that was easy. I have a PWM spare controller but it won't work with my 24v panel unless batts are 24v too, so I needed to test that.
Then I thought this might be a way to beat my usual dismal MPPT results in July August with 24-12 when I knew PWM at 12-12 would do better. I never thought of MPPT 24-24 as the work-around.
The snag now seems to be not getting the full panel amps through the PWM at 24-24 I would expect from my 12-12 results before. That may in fact be due to the 60 cell/72 cell thing, I don't know. To Be Determined!
12v MPPT- 12.7v/14.97a (190w)
24v MPPT- 25.6v/7.95a (203w)
24v PWM-- 25.5v 7.99a (204w)
Same equality for the two 24s as this test, but this time I didn't do the 24-12 MPPT.
I want to compare them all at 50C instead of at 44C to see if it would be worth the trouble to go 24v and PWM. So far it looks like going 24v is the point and it makes no diff PWM or MPPT.
This all started when Mr Wiz had to go PWM as his spare controller when his MPPT died on him. He has a 12v array so that was easy. I have a PWM spare controller but it won't work with my 24v panel unless batts are 24v too, so I needed to test that.
Then I thought this might be a way to beat my usual dismal MPPT results in July August with 24-12 when I knew PWM at 12-12 would do better. I never thought of MPPT 24-24 as the work-around.
The snag now seems to be not getting the full panel amps through the PWM at 24-24 I would expect from my 12-12 results before. That may in fact be due to the 60 cell/72 cell thing, I don't know. To Be Determined!
