"Overflow" reading on a capacitance tester - what does it mean?

Discussion in 'The Projects Forum' started by kcroy, May 3, 2014.

  1. kcroy

    Thread Starter New Member

    Dec 24, 2011
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    I am testing the capacitor in a speedlite 420ex camera flash. I have drained the cap.

    I am using a cheapie Jinyang 6013 cap tester ( .01-4mF ) and it shows a result of "Overflow".

    - what does that mean?

    I am testing it in-circuit, do I need to pull it out completely?

    Thanks in advance!
     
  2. RamaD

    Active Member

    Dec 4, 2009
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    You need to take it out the capacitor. I think the measurement technique used in this meter is to pass a constant current and measure the time taken to reach a threshold voltage.
     
  3. DickCappels

    Moderator

    Aug 21, 2008
    2,651
    632
    Generally, overflow means that the value to large to be measured. Check the manual against the value of the value printed on the capacitor.

    Don't know whether testing it in-circuit could produce that reading, but its best to test out of the circuit because you don't know how the other components will affect the measurement.
     
  4. kcroy

    Thread Starter New Member

    Dec 24, 2011
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    OK thanks I'll take it out and try it.

    However, I think maybe my tester doesn't have the correct range. The cap should be 1150uF/330V.

    Regarding the range of cap tester... it says: 0.01pF to 47mF ... but perhaps that is a mislabelled 47uF...
     
  5. RamaD

    Active Member

    Dec 4, 2009
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    You could easily check out the limit of the range with some spare capacitors (not connected to the circuit, though), avoiding the bother of desoldering!
     
  6. bertus

    Administrator

    Apr 5, 2008
    15,647
    2,346
    Hello,

    Most manuals of capacitor testers will tell you that there may not be any charge in the capacitor.
    Always discharge the capacitors before you use them on a tester.

    Bertus
     
  7. kcroy

    Thread Starter New Member

    Dec 24, 2011
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    yes, thanks, I will try that tomorrow.
     
  8. MrChips

    Moderator

    Oct 2, 2009
    12,440
    3,361
    So unknowledgeable folks incorrectly use mF to mean μF.

    47mF should mean 47000μF.
     
  9. Johann

    Senior Member

    Nov 27, 2006
    190
    30
    This range is suitable for testing the cap you wanted to test. (If it indeed means milli-farad! - might be, otherwise you are just out of the meter's range). If the meter can actually read up to 47 mF, it indicates a short circuit or leakage in the cap.
     
  10. DickCappels

    Moderator

    Aug 21, 2008
    2,651
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    In an earlier time in the United States, "mf" meant "microfarads" and "mmf" meant milli-microfarads (pf today). And we used "kc" for "kilocycle". So there you go, young whipper-snapper! :)
     
  11. crutschow

    Expert

    Mar 14, 2008
    13,003
    3,232
    I remember that. But mmf would be micro-micro farads (pF). Milli-microfarads would be nF.
     
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  12. KeepItSimpleStupid

    Well-Known Member

    Mar 4, 2014
    1,144
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    I remember mfd in the old Sam's photofacts. I used to have an AM/FM/SW tube car radio that was marked in wavelength, so the dial, was, in fact, backwards.

    There was a major effort to stadardize units in my time and what came out of that was the mks and cgs systems and the honoring of inventors by capitalizing their names. Volts, Farads and Siemens come to mind. The mho (ohms spelled backwards) was renamed the Siemen.

    The stardard prefixes came in to use too, such as nano, micro and pico.

    ms is milliseconds and mS is millisiemens and mHz is millihertz and MHz is Megahertz. mhz isn't a unit.
     
  13. kcroy

    Thread Starter New Member

    Dec 24, 2011
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    ok .. it's been longer than "tomorrow"! But I did test with some other caps. There was a selecter for choosing range - once I set it to Auto, I was able to test some caps out in the 6800 uf range. So I'm onto the next step of pulling the cap, and testing it again.
     
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