Relay Suppression
Relay Suppression
(OP)
I am looking for information regarding relay suppresion. I have read about various different types that can be used, I'm curious what situations you would use the different types in. For example MOV's, Snubbers, Diodes etc.... Also how do you size the suppression correctly? I seem to get different answers from my colleagues and as im only two years out of my time i see it best to learn the correct ways now than "Wild Guessing".





RE: Relay Suppression
Russell White, P.E.
Automation Technologies, Inc.
www.AutomationNC.com
Automation Help
www.PLCMentor.com
RE: Relay Suppression
RE: Relay Suppression
I assumed he was interested in protecting a source against inductive backlash from the coil. I should be clear that my comments are for MOVs/diodes installed in parallel with the coil for this purpose.
Russell White, P.E.
Automation Technologies, Inc.
www.AutomationNC.com
Automation Help
www.PLCMentor.com
RE: Relay Suppression
RE: Relay Suppression
MOVs protect the device from problems in the circuit.
RC Snubbers protect the circuit from problems in the device.
Not universally true of course, but it works.
By the way, I dislike MOVs in general because of their failure mode. I have spent a LOT of time and money cleaning up messes caused by vaporized MOVs.
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
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RE: Relay Suppression
RE: Relay Suppression
Yes, I know that's not the fault of the MOVs, they were just doing their job. But still, their mode of "sacrifice" left a little to be desired.
"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies
RE: Relay Suppression
Russell White, P.E.
Automation Technologies, Inc.
www.AutomationNC.com
Automation Help
www.PLCMentor.com
RE: Relay Suppression