What's the difference here?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by TweeDLX, Feb 9, 2012.

  1. TweeDLX

    TweeDLX Member

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    This morning I was looking at electrolytic caps and noticed that they had different voltage ratings.
    Specifically: WVDC & SVDC with the SVDC rating being slightly higher.
    What do the W & S signify? Thanks for your clarification.
     
  2. jitterbug

    jitterbug Member

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    W is working voltage and S is surge voltage. The working voltage tells you how much voltage the capacitor can withstand for the normal life of the capacitor. The surge voltage is the voltage that the cap can withstand for short periods of time. I worked on some amps earlier last year that had screen voltages of 485 volts yet had supply caps that were rated 450. They were going on the road for a few months so I changed them all out. Four amps total.
     
  3. teemuk

    teemuk Member

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  4. TweeDLX

    TweeDLX Member

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    Thanks for your reponses! Another piece of the puzzle in place! You guys rock!
     
  5. donnyjaguar

    donnyjaguar Member

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    Marketing nonsense. There's no such thing as SVDC. All electrolytics can tolerate higher than spec'd DC voltage for short duration.
     
  6. Patrick620

    Patrick620 Member

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    I have wondered the same thing on occasion. Good question and answers. Thanks
     
  7. SatelliteAmps

    SatelliteAmps Member

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    Not quite nonsense or marketing. Surge voltage is supposed to be saying what the top of a surge should be on the capacitor without affecting it's failing or lifetime. There is a limit.
     
  8. Ronsonic

    Ronsonic Member

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    While it's true that all caps can tolerate a short term over-voltage, it once was a commonly shown spec and now isn't. Most of the e-caps I see from the 50s are marked with a SVDC
     
  9. diagrammatiks

    diagrammatiks Member

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    most caps worth their salt have it labeled in the datasheet along with expected lifetime hours of continued operation at svdc.
     
  10. TweeDLX

    TweeDLX Member

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    Interesting stuff here. I had seen the WVDC before and never really thought about it until I saw the SVDC rating.
     

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