I have a 6 year old MPTT 100/30 charge controller that I stopped using about 3 years ago since I could not tighten the PV+ terminal screw anymore and I needed a more powerful unit anyways. As I want to use it for a different project I tried to loosen it again today but no matter what I tried the thing was stuck. Finally I got the cover of, and cut open the side of the connector and the thing is just completely oxidized.
I am going to try and find similar terminals to replace it (if someone knows which type they are I am listening) but anyone any idea why this thing is so rusty ? It was never in contact with water unless maybe condensation, but all the other terminals are in pristine condition so I would expect them to be affected too if it is condensation. Some kind of chemical reaction that only happens at PV+ ?
I would like to understand the issue to make sure it does not happen to my much more expensive current unit.
Googling the problem does not give me any hits.
EDIT: I just found the terminal on farnell, it is a MULTICOMP PRO MC000232
