Regarding Solid-state Relays: SSRs are *the* way to go. The major
problem is finding a source for them, as they are very much a "specialty"
item, even in the electronics/electrical world. I'd call DigiKey,
1-800-344-4593 , and ask for a catalog. There is a huge selection of
Crydom SSRs in the catalog -- and at DigiKey you can order small
quantities! A properly selected SSR will last essentially forever. They
are not a "restoration" item of course; they're new technology.
For a perfect restoration, you'll have to rebuild the old relays.
A few (a very few) motor rebuild shops can do this for you if they have
absolutely nothing better to do.
Regarding "melting" relays: there is indeed a problem with the newer,
cheap-o relays commonly sold, even if they have silver contacts. The
answer is either a SSR (above) or a high-quality "contactor" type of
relay designed for motor switching. A motor-switching relay can and
should last decades if it is selected with the appropriate rating (which
for me is double- everything!). Think of your refrigerator: it uses a
motor relay -- and you never unplug it.
Grainger's Motor Supply (Yellow Pages) has pages and pages of
motor-control relays in their catalog. Just select twice as big a relay
as you think you need. They're big and ugly and not an aesthetic or
restoration replacement, but -- safety first!
My two cents....
Pat Mullarky
Patrick Mullarky
NW Computer Engineering
pat@nwce.com www.nwce.com
206 451-7916 206-453-9699 fax
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