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.
How to test solar panel diode.
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.
E marine walks you through testing a solar panel s output to make sure it s performing correctly.
Multiply that number by 0 4 volts to find the amount of voltage that should cause the bypass diodes to become conductive.
Feel free to ask any doubts regarding this video.
In this video i am explaining why bypass diode is used in a solar panel.
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.
Make sure it is actually installed the right way.