Mechanical Music Digest  Archives
You Are Not Logged In Login/Get New Account
Please Log In. Accounts are free!
Logged In users are granted additional features including a more current version of the Archives and a simplified process for submitting articles.
Home Archives Calendar Gallery Store Links Info
MMD > Archives > June 1997 > 1997.06.27 > 07Prev  Next


Electrical Safety - Solid State Relays
By Pat Mullarky

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


(Message sent Fri 27 Jun 1997, 19:02:08 GMT, from time zone GMT-0800.)

Key Words in Subject:  Electrical, Relays, Safety, Solid, State

Home    Archives    Calendar    Gallery    Store    Links    Info   


Enter text below to search the MMD Website with Google



CONTACT FORM: Click HERE to write to the editor, or to post a message about Mechanical Musical Instruments to the MMD

Unless otherwise noted, all opinions are those of the individual authors and may not represent those of the editors. Compilation copyright 1995-2024 by Jody Kravitz.

Please read our Republication Policy before copying information from or creating links to this web site.

Click HERE to contact the webmaster regarding problems with the website.

Please support publication of the MMD by donating online

Please Support Publication of the MMD with your Generous Donation

Pay via PayPal

No PayPal account required

                                     
Translate This Page