diy solar

diy solar

MC4 Connectors exposed to moisture - Degraded Panel output


New Member
Oct 11, 2019
Hi - I have a sailboat that is hauled out for the winter and the solar panels are disconnected and stored. I realize the solar wire (not plugged) has exposed the contacts to corrosion.

Is there a way to test for corrosion to see if this is why the panel (sunpower semiflexible 110W - 4 years old) do not generate as much power as they used to?
Is the best option to cut and recrimp new connectors and perhaps use the old connectors as plugs to help protect the contacts over the winter?
Finally what is a good source for quality MC4 connectors (I am in Canada if that helps) I am leery of the variable quality you find on Aliexpress and even Amazon now.
Stabuli is the official manufacturer for MC4, so I’d try that.

You can look at the connector to see corrosion. You can also try to clean with rubbing alcohol and an acid brush, or any othe brush.

You could cut them.

Your idea of using the old connectors after you replace them seems better than the MC4 plugs I bought whic were rubber caps and did not look watertight.

4 years is nearing the limit for a flexible panel.
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