checking capacitor with multimeter

Discussion in 'General Electronics Chat' started by paulwma, Sep 6, 2012.

  1. paulwma

    Thread Starter New Member

    Sep 6, 2012
    1
    0
    I been trying to repair the power supply for my Plasma tv 42PF7520D/10
    I been told its one of the capacitors that has blown.
    I cant see any visual damage to any of the capacitors.
    I used my multimeter to check the capacitors. I selected 2000k ohms
    I connected the probes to the capacitors and i could see them charging, numbers rising on my digital meter.
    But two of the capacitors when my meter was connected didn't start to charge meter didn't do anything. when i reversed my meter probes the two capacitors started discharging
    Are these two capacitors faulty?
     
  2. MrChips

    Moderator

    Oct 2, 2009
    12,442
    3,361
    You cannot reliably test capacitors in circuit.
    Unsolder the capacitors and remove from the board, if that is an easy operation.
     
  3. nigelwright7557

    Senior Member

    May 10, 2008
    487
    71
    I would recommend a cheap LC meter to test capacitors out of circuit.
    I have seen them for less than £20.
     
  4. vegeta

    New Member

    Sep 7, 2012
    6
    0
    I would take the capacitors out of the circuit if possible and then measure the impedance. There are probably too many components in circuit to get an accurate measurement.
     
  5. ramancini8

    Member

    Jul 18, 2012
    442
    118
    I wouldn't check the capacitors, I would replace them.
     
  6. tester272001

    New Member

    Aug 24, 2012
    18
    0
    You could also use an ESR meter to test the caps in circuit. Or if you have a scope put that on the caps and look for AC or high ripple.
     
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