Arc supression cap

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I've always replaced defective suppressor caps on switches with 0.047uF 630v poly caps and never had an issue.
Of course, you'll get a slew of responses next for those "x" rated caps by the adament purists.
But since these caps are not used directly across the line, an "x" cap is not a requirement.
 
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I have some 250V caps on hand, is that too low to account for inrush/surge?


Yes.
I prefer to use the 630v rating caps to insure reliability. (for 120v equipment)

Like I said before, never had an issue that way.
Having to work on customer equipment for decades, and considering liability issues, I want my customers to be satisfied, I don't need lawsuits.
 
What do you think of wiring a 47ohm, 0.5W metal film resistor in series with the 0.047uF film capacitor, wiseold?

If the film capacitor ever did fail short circuit, the metal film resistor would act as a fuse, burning out and shutting off the short circuit current.

That's certainly how it was done in my 60's valve amplifier, although I concede we have more reliable, higher working voltage film capacitors nowadays.
 
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What do you think of wiring a 47ohm, 0.5W metal film resistor in series with the 0.047uF film capacitor, wiseold?

If the film capacitor ever did fail short circuit, the metal film resistor would act as a fuse, burning out and shutting off the short circuit current.

That's certainly how it was done in my 60's valve amplifier, although I concede we have more reliable, higher working voltage film capacitors nowadays.


I've never had to add a resistor, just the cap across the switch terminals.
Most manufacturers have done the same thing.
However, if one wants to play around with things, let them.
 
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What do you think of wiring a 47ohm, 0.5W metal film resistor in series with the 0.047uF film capacitor, wiseold?

If the film capacitor ever did fail short circuit, the metal film resistor would act as a fuse, burning out and shutting off the short circuit current.

That's certainly how it was done in my 60's valve amplifier, although I concede we have more reliable, higher working voltage film capacitors nowadays.

To be clear, do you mean 630VDC rating, wiseold?


Yes, DC, to be clear.
Buy yourself a bag of these and you'll be fine.
 

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