Date: Wed, 10 Jun 2009 09:23:20 -0500
Reply-To: John Rodgers <inua@CHARTER.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John Rodgers <inua@CHARTER.NET>
Subject: Re: Correct use of Dielectric grease?
In-Reply-To: <38e334640906092207r3ea13dfcs7460279a59cd9ee7@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
The term dielectric is confusing.
From Wikipedia:
>>A *dielectric* is a nonconducting substance, i.e. an insulator. The
term was coined by William Whewell in response to a request from Michael
Faraday. Although "dielectric" and "insulator" are generally considered
synonymous, the term "dielectric" is more often used to describe the
insulating material between the metallic plates of a capacitor while
"insulator" is more often used when the material is being used to
prevent a current flow across it.<<
Dielectric grease is non-conductive yet it transfers heat. Dielectric
grease is often used with a heat-sink to transfer the heat better and it
can also be used in applications where electrical components might get
damp and/or hot and corrode. Most auto manufacturers are using
dielectric grease or other grease compounds to protect light sockets and
other electrical connections. The protection from corrosion ultimately
prevents the heat that can occur in a corroded connection that
eventually leads to a melt down or fire.
Check this Youtube video.
http://www.ask.com/bar?q=dielectic+grease&page=1&qsrc=0&ab=2&u=http%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D8W7o-CRRmGo
*http://tinyurl.com/lrcdoy*
The electricians from the Power Company came and did some work and they
used dielectric grease on the heavy connections where aluminum wiring
was clamped. My electrician did the same thing with both aluminum and
copper wiring. Aluminum is more troublesome than copper, as it has a
far greater tendency to corrode and get hot than copper.
Corroded contact points offer resistance to the current and heat is the
result. The dielectric grease, while it does not conduct electricity
itself, inhibits that corrosion that does resist current flow and
results in heat.
There are conductive lubricants used to aid current flow, but they are a
different class of materials - not dielectrics.
John Rodgers
88 GL Driver
Roland wrote:
> Hello folks,
>
> I was reading the discussion about high powered headlights overheating some
> connectors, and again I saw mention that use of dielectric grease is good
> practice. .... to put it on the contacts. Of course I've seen it
> referenced many times.
>
> But this confuses me. Dielectric grease is an insulator, right? It is
> non-conductive. Why would we put it on the contacts where we want a better
> connection? Why wouldn't we use conductive grease on contacts? Or is the
> proper application of dielectric grease to put it on the outside of the
> connector, but never on the contact points themselves? I keep a tube of
> conductive grease around the garage, use it only very rarely. If we use
> dielectric grease only on the outside of a connection, why not just use heat
> shrink tubing?
>
> Thanks!
> Roland
>
>
>
