As most solar panels are 12 volts the solar panel test methods are basically the same.
How to test solar panel diode.
E marine walks you through testing a solar panel s output to make sure it s performing correctly.
If you find this video helpful pl.
The blocking diode should be installed with the silver ring facing away from the panel toward the output connection towards positive some diodes may have an arrow pointing in the current flow.
You will want to ensure that you place the positive to positive and negative to negative when attaching your multimeter to the connection on the back of your solar panel.
Feel free to ask any doubts regarding this video.
Before conducting the test you should know how many solar panels were connected in series in the string in question and how many bypass diodes each panel has.
In this video i am explaining why bypass diode is used in a solar panel.