When adding a .01 cap across a switch to suppress arcing, what is the proper voltage rating of the cap for 120 vac line voltage?
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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.
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.
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.
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.
The problem with a transformer is you can get high back emf's when you turn it off.
The previously recommended 630VAC or higher cap is the best solution.
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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