SCR application in relay replacement

Thread Starter


Joined Jan 31, 2009
Ref: Your Chap % section on electro-mechanical relays & SCR equivalents.
Well I find the explanations close to the limit of what I can absorb.
I note the frequent assertion (here & elsewhere) that "digital relays" (IE scr's) are inherently better having no moving parts, & no contact sparking.
It's usually claimed that they are inherently lower cost.
But recently my deep freeze switching relay burned out due to contact carbonisation. It looked about 5$ value but I was amazed to learn a replacement was not available. (Chinese product !!). Anyway I was offered an 80$ digital replacement.
Not likely I just made a good job of cleaning up the old relay, used epoxy to fill the burned housing & its all go. Can't say I expect many more years but it made me wonder why a general purpose conventional relay was not offered.
Having read the material here on SCR's I am no nearer understanding how I could use one, or a pair, to replace the relay I repaired.
Explanations of function are worthless if the reader cannot then employ the knowledge made available. Sure I am not the brightest on this subject, but it seemed to me this did warrant an "applications" addition to the existing material.
Anyone choose to help?


Joined Mar 24, 2008
Feedback and Suggestions Forum for providing feedback and suggestions about All About Circuits, including corrections to the e-book. This forum is not for getting help with technical questions.
I am moving this to the more appropriate forum where you are likely to get more help.

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