Schottky Diodes

I took a second look at measuring the leakage current of the Renogy solar panel - that first reading of ZERO current kinda bugged me.

https://wb9kzy.blogspot.com/2026/05/the-renogy-solar-panel-dischargeleakage.html 

I used the newer Triplett DVM just in case there was some kind of problem with the Metex used before.

  At 12.84 volts I again measured zero current in any of the three ranges.

So I was thinking about that and this is my surmise: there are lower voltage Schottky diodes like the 1n5818, 1 A diode I used on the other solar panel.  The low voltage diodes have somewhat high leakage currents.  Then there are higher voltage Schottky diodes for use in switching supplies and the like.  They have higher forward voltages but smaller leakage currents.  Here is part of a Nexperia Schottky diode data sheet:

I will have to pay the tariff tax and get some of these

How does this fit in with the Renogy solar panel ?  The Renogy has 72 solar cells which I assume are used in two parallel strings of 36.  Remember that the other panel only had 32 solar cells in series.  So maybe Renogy designed in 4 solar cells of "headroom" to use the higher voltage / lower leakage diode which accounts for the zero leakage current measurement ?

There's always a tradeoff, no matter what !  :)

Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm