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
It is no wonder Salvo is getting mixed up in what I was saying, but I did try to make it clear! :(
The idea was to get the same performance (amps to the battery) with the 24v as I got with 12v. So that means half the amps with the 24v
Then it turned out the 24v panel has a higher Isc per wattage than the 12v panel does. Eg, my 130w did 8.2 amps to battery (same as its Isc value) so I would expect a 260w panel to crank out 8.2 amps too. Two 130s would get me 16.4 amps
But the Isc of my 255 is 9 amps so I was hoping to get equivalent to 18 amps, a bonus in amps (18 vs 16.4) by using PWM 24-24 compared with 12-12.
Didn't happen. I might still do as well with the PWM on 24 but with no bonus. With the hot panel and MPPT doing 13.5 instead of PWM's 14.5 last summer, I could still see PWM on 24 doing better than the MPPT on 12, but now it looks like the MPPT on 24 could do that too, due to the higher loss 24-12.
Just have to see what happens at 50C panel.
The idea was to get the same performance (amps to the battery) with the 24v as I got with 12v. So that means half the amps with the 24v
Then it turned out the 24v panel has a higher Isc per wattage than the 12v panel does. Eg, my 130w did 8.2 amps to battery (same as its Isc value) so I would expect a 260w panel to crank out 8.2 amps too. Two 130s would get me 16.4 amps
But the Isc of my 255 is 9 amps so I was hoping to get equivalent to 18 amps, a bonus in amps (18 vs 16.4) by using PWM 24-24 compared with 12-12.
Didn't happen. I might still do as well with the PWM on 24 but with no bonus. With the hot panel and MPPT doing 13.5 instead of PWM's 14.5 last summer, I could still see PWM on 24 doing better than the MPPT on 12, but now it looks like the MPPT on 24 could do that too, due to the higher loss 24-12.
Just have to see what happens at 50C panel.
