Voltage of stored capacitors

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  • yyonline
    Badcaps Veteran
    • Jul 2009
    • 692
    • USA

    #1

    Voltage of stored capacitors

    So I was bored today and was messing around with a new multimeter. I tested some of the caps I had in storage as I was curious how long some of the larger ones from power supplies and the like held a charge.

    Then, just out of boredom I started testing some of the smaller caps I have in my spare parts pile. Well, much to my surprise, I have a bunch of 6.3V 1000uF Rubycon that all measured about 0.25 V. I shorted the leads on a few of them, measured again, and the voltage dropped to 0 as expected. I come back a few hours later and they're 0.25 V again. These are about 3 years old, but unused still on the tape and reel.

    A few questions from the electronics ignorant me...

    Where is it picking up this voltage from? And does it mean anything? None of the other capacitors I have seem to do this, so I was just wondering if it could mean something is wrong with them.
  • stj
    Great Sage 齊天大聖
    • Dec 2009
    • 30979
    • Albion

    #2
    Re: Voltage of stored capacitors

    nothing wrong with them,

    Comment

    • PCBONEZ
      Grumpy Old Fart
      • Aug 2005
      • 10661
      • USA

      #3
      Re: Voltage of stored capacitors

      They are fine.
      The construction and chemistry is loosely similar to a battery and all that's going on is some charged particles are moving around between the electrolyte and plates.
      .
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