Old electrolytic capacitors

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  • alfredo2j90
    New Member
    • Oct 2021
    • 4
    • Australia

    #1

    Old electrolytic capacitors

    So as most of us know, old unused electrolytic capacitors are unrealiable due drying out and breakdown of the oxide layer.

    I have a few questions regarding these issues.

    1. Does using an electrolytic cap stop it from drying out or is it natural process that happens regardless?

    2. With the breakdown of the oxide layer the ESR will increase as well as DC leakage. Say the cap has remained unused on a motherboard, psu or games console for many years, if the cap does not physically pop when power is applied what other damage could occur to the system if it was powered? Does the increased ESR and DC leakage damage the mobo, psu or games console or is the repair as simple as replacing the cap?
    Last edited by alfredo2j90; 10-10-2021, 05:20 AM. Reason: Extra info
  • AleXis6
    Senior Member
    • Feb 2021
    • 69
    • Belarus

    #2
    Re: Old electrolytic capacitors

    1. As a read producers adviced to keep capacitors in ziplock packs to prevent shortage of their life
    2. I bought LCR meter and evaluate the capacity, ESR, Z, D and other parameters and compare measured numbers to datasheet.
    DC leakage is easy to measure just with a millivoltmeter.
    Capacitors with high ESR will not necessarily fail immediately, but the operation of the equipment may be unstable, the symptoms will increase over time and under heavy load. If you replace a bad capacitor in time, you do not need to change the other components.

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