I have a microwave where the thermal switch keeps tripping, but looking at how burnt the external contacts are I think it is they that are tripping the switch and not the microwave itself; so I worry about contact resistance for modular connectors on power supplies and the heat they produce.

How come they never seem to be gold plated? that might help with the corrosion that is probably responsible for much of the contact resistance.

I'm a big one or silicone oil as stabilant 22 is out of budget for me.