I have built four or five "stack matches" using these relays and have been
quite pleased with them.
http://www.mouser.com/ProductDetail/TE-Connectivity/T92S11D22-12/?qs=%2fha2pyFadujQKxyiQ9QJsU9gOmzykpctnwthD3xoZjoJPHbNrun4hw%3d%3d
73...Stan, K5GO
If you look at the contact material, it is the wrong material type for our
applications. Those relays are hot switch relays for high current
applications with Silver Cadmium Oxide. From an engineering bulletin on
selecting relay contact materials:
Silver Cadmium Oxide
Silver cadmium oxide contacts have long been used for switching loads
that produce a high energy arc. Silver cadmium oxide contacts are less
electrically conductive than fine silver contacts, but have superior
resistance to material transfer and material loss due to arcing. They do
exhibit greater interface resistance between mated contacts, and also a
slightly greater contact assembly heat rise. The minimum arc voltagerating
of silver cadmium oxide is 10 volts and, like fine silver contacts, the
silver
in this alloy will oxidize and sulfidate. Therefore, an arc is necessary to
keep these contacts clean.
This doesn't mean they won't work and will go up in smoke. It does mean they
are subject to contact sulfidation which causes intermittent receive. They
have silver, a hard base material, and large contact area that does not wipe
well. They also are the type of relay that is subject to contact derating
from skin effect because of constant resistivity.
73 Tom
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