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...
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I was able to use Salvo's method (as I call it since he posted how to do this a while ago) to identify where the losses are in the path.
I replaced one lead on the multi-meter with one I made from a long speaker wire with a clip on its end, so I can measure the voltage drop from one end of a long wire to the other when there is a known current on that wire. This gets you the actual V from the meter and then you can calculate the R, but here I just wanted the V.
The path is in three sections: Panel(P) to connections A, then to B, then to controller C. I had a steady 15 amp output over the time it took so that would be a steady 8ish amps along the path for all measurements.
P-A Pos 0.07, Neg 0.15 = 0.22
P-B Pos 0.14, Neg 0.21 = 0.35
P-C Pos 0.23, Neg 0.29 = 0.52
That total of 0.52 goes with my first look 29.0v at panel and 28.5v at controller for Vmp at the time. I can now see where to go to clean up the path that would do the most good.
Thanks again, Salvo! :)
I replaced one lead on the multi-meter with one I made from a long speaker wire with a clip on its end, so I can measure the voltage drop from one end of a long wire to the other when there is a known current on that wire. This gets you the actual V from the meter and then you can calculate the R, but here I just wanted the V.
The path is in three sections: Panel(P) to connections A, then to B, then to controller C. I had a steady 15 amp output over the time it took so that would be a steady 8ish amps along the path for all measurements.
P-A Pos 0.07, Neg 0.15 = 0.22
P-B Pos 0.14, Neg 0.21 = 0.35
P-C Pos 0.23, Neg 0.29 = 0.52
That total of 0.52 goes with my first look 29.0v at panel and 28.5v at controller for Vmp at the time. I can now see where to go to clean up the path that would do the most good.
Thanks again, Salvo! :)
