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Re: (ET) Dielectric grease



In my opinion (shared by others with far more experience than me) it's a good idea to put grease, dielectric or otherwise, on contact surfaces.
 
Sometimes.
 
I always smear a thin coat of Vaseline or Noalox (or something similar) on battery terminals before installing a cable, and on the stripped cable end before crimping on a connector.  There are inevitably many gaps that exist in these joints, even though they are formed under high pressure.  The grease fills them in throughout the joint.  At the microscopic level, contact between two surfaces is actually between the peaks of the two objects' surface roughness.  Since grease is a high-viscosity fluid, it will flow away from the points of contact and completely surround them.  This is especially helpful with battery terminals - can you really get grease between terminal and lug under the joint after you've installed the lug?  I doubt it.  With my method the grease squeezes out from within the joint to seal everywhere.
 
I've never had a problem with this.
 
Having said all that, I would not use grease on relay contacts.  They are meant to be held together with relatively light pressure.  I'd be worried the thick grease wouldn't flow well enough to allow good contact.  And also attract dust.
 
Chris

On Sun, Oct 11, 2009 at 6:25 PM, RJ Kanary <rjkanary consolidated net> wrote:
First let's look at what Dielectric means.

http://en.wikipedia.org/wiki/Dielectric


The, let's look at what dielectric grease DOES.

http://en.wiktionary.org/wiki/dielectric_grease

        Now we know what it DOES. This should influence how and where we USE it.

    Since it inhibits electron flow, having it between two points in a circuit is a BAD thing.On the outside of connections to prevent moisture incursion and corrosion is GOOD. On relay contacts is BAD.On the outside of terminals slid on the relay connections is GOOD. On the terminals before a connection is made is BAD.

And yes, I was thinking of you, Jerry. :)

[Inside joke.]

RJ


Bill Alburty wrote:
Should it be used on battery  terminals and open relay contacts of our ETs? Its an insulator meant to keep out moisture and corrosion, but how good is the electrical conduction of the contacts when it is used?  What do you guys advise?
Thanks,
Bill Alburty E-12 KS

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