LV measurement of HV caps

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  • Behemot
    Badcaps Legend
    • Dec 2009
    • 4845
    • CZ
    #1

    LV measurement of HV caps

    I think this method is just too unprecise from principle even though I do not know why. Do the caps have higher leakage with high voltage applied? So with tiny voltage (ESR Micro uses about 0.2 V) it has lower leakage and lower apparent capacity? I guess so.

    Just tried Chemi-Cion KMR 330/45 date code 3DVL4M with both ESR Micro v4.0s, v4.0si and UNI-T UT210E. Result is 281, 294 and 293 uF.

    I don't think this is capacitor problem, I have constant results for years.
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    • stj
      Great Sage 齊天大聖
      • Dec 2009
      • 30979
      • Albion
      #2
      Re: LV measurement of HV caps

      different test frequency's maybe.

        Comment

        • Andrew F. Ali
          Badcaps Legend
          • Jan 2014
          • 2450
          • Trinidad & Tobago
          #3
          Re: LV measurement of HV caps

          I think the frequency of the test voltage has something to do with it also....just sayin

            Comment

            • Behemot
              Badcaps Legend
              • Dec 2009
              • 4845
              • CZ
              #4
              Re: LV measurement of HV caps

              Frequency of DC?
              Less jewellery, more gold into electrotech industry! Half of the computer problems is caused by bad contacts

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                Comment

                • stj
                  Great Sage 齊天大聖
                  • Dec 2009
                  • 30979
                  • Albion
                  #5
                  Re: LV measurement of HV caps

                  dc? esr meters use squarewave pulses to simulate ac.

                    Comment

                    • Behemot
                      Badcaps Legend
                      • Dec 2009
                      • 4845
                      • CZ
                      #6
                      Re: LV measurement of HV caps

                      Who's talking about ESR? Have you noticed those capacitance figures?
                      Less jewellery, more gold into electrotech industry! Half of the computer problems is caused by bad contacts

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