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Using no gold plated contacts instead of original gold plated contacts

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I don't understand how even a worst-case few ohms of resistance from corrosion would make a difference to a low-current, high-impedance input.  Without doing the math, I could imagine problems with CAN or high-current outputs, but not inputs.  Maybe with high-speed frequency inputs.  Could someone explain the issue from an electronics circuitry perspective?  How much additional impedance would an aged tin-plated Deutsch pin introduce to the circuit?

This is a Physical thing:  Whetting is caused by a sort of "surface tension" between contact points.

I didn't know that a minimum current to "break through"an oxidation layer applied to contacts already in place.  I always thought of wetting current in terms of relay contacts that develop a small corrosion layer when apart then come straight together without any sliding or scraping like a connector pin. 

The Deutsch Common Contact System Technical Manual does not specify a minimum current, but does state:
--- Quote --- Gold plating is available for dry circuit applications
--- End quote ---
Unfortunately I could not find an industry-standard definition of "dry" (or wet) circuits, with manufacturer current levels ranging from 0.5 to 100mA.  Since Danfoss says their high-impedance inputs are dry by Deutsch standards, I'll switch to using gold plated contacts when appropriate.


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