Interesting what the article says about gold not being as durable as silver=
 under=20
arcing conditions.

I had wondered once if gold plating over standard contacts in a power relay=
 might=20
bring some benefit... allow them to be used at microamp levels without oxid=
isation=20
problems, or if used at high currents the gold might disperse harmlessly an=
d fall=20
back to working on the silver alloy underneath. Thoughts? For the applicati=
on I had=20
in mind the current was not known precisely as it depended on the equipment=
 the=20
user would install it into... could be some hundreds of uA, or some 10's of=
 Amps, but=20
whatever it was once installed the conditions would remain consistant.

On 19 Oct 2013 at 12:49, John Ferrell wrote:

> As an old time relay mechanic at IBM my diagnosis is simply proper=20
> adjustment is needed.
> There should be enough over travel of the moving contact to assure there=
=20
> is a little "wiping" action of the contacts.
>=20
> On 10/19/2013 11:57 AM, Peter wrote:
> > http://www.eetimes.com/author.asp?section_id=3D30&doc_id=3D1319831&
> >
> > Worth reading for anyone using relays in small signal circuits. My solu=
tion
> > would have been to analyze the circuit and add small caps (100n) across=
 the
> > low current contacts, assuming the rest of the circuit would have worke=
d
> > with the additional delay. These will charge to supply voltage and prov=
ide a
> > nice tiny cleaning arc upon contact closure, keeping the low signal sid=
e
> > reasonably clean. No idea if it would keep like this, it is a hack, but=
 ...


--=20
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