Tom Yang wrote:
> Ron,
>
> I'm trying to find something that will help a Lucas made windshield wiper
> switch perform better. This rotary switch seems to have a tendency to arc,
> and oxidize the contacts. I've cleaned everything with fine sandpaper, but
> can still see the arcing. Eventually, this will cause the switch to fail
> again. "(Where are all those electrical engineers when you need them!)!"
>
> Tom
>
> Message text written by INTERNET:tebomr@cadvision.com
> >Tom:
>
> (Where are all those electrical engineers when you need them!)
> I have always been curious about this too, since my understanding of the
> word "dielectric" is that it is non-conductive, since that is what the
> material used to separate the two conductor halves of a condenser is
> called. However, when I questioned using it on low voltage batteries (in
> one
> of my past incarnations as a railway signal maintainer), I was told that it
> was non-conductive, but the mechanical forces of the connection were
> sufficient to punch through the film of grease, and avoid any major voltage
> drop. Also, it is non- conductive to avoid any leakage of the terminal
> voltage to ground through the grease residue.
>
> If this is true, then this may not work well in a switch (contact pressure
> is usually pretty low and you may get a high voltage drop due to increased
> resistance -no short)
>
> There is a type of conductive grease that we used to use on relay contacts
> that were subject to wear and corrosion, but I have no idea what it is
> called. (I believe model railroad guys used to bum small amounts to use on
> their outdoor tracks, so you might try them).
>
> This is all I know, and maybe those engineer guys can correct my mistakes!
>
> Ron Tebo
>
> <
Tom:
If we had one of those engineer guys available....(sigh).... they could
probably tell you where to install a condenser (and what value) to stop the
arcing without affecting performance!
Ron Tebo
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