Repairing shunt in DVOM??

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  • asand1
    Oregon, USA
    • Oct 2011
    • 123

    #1

    Repairing shunt in DVOM??

    I have a generic DVOM that is having issues. It wont read volts or Ohms, but it will read zero Ohms when shorting the leads. The shunt inside looks to be burnt. Can I use solid copper wire to replace it?
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  • retiredcaps
    Badcaps Legend
    • Apr 2010
    • 9271

    #2
    Re: Repairing shunt in DVOM??

    Originally posted by asand1
    I have a generic DVOM that is having issues. It wont read volts or Ohms, but it will read zero Ohms when shorting the leads. The shunt inside looks to be burnt.
    1) Can we get a picture of the front of it so we can see the brand name and model number?

    2) To measure volts and ohms, the current shunt is not used at all. Do not replace the shunt with a copper wire.

    3) In cheaper multimeters, the current shunt usually looks like crap. From the picture, it looks normal to me.

    4) If you try to measure an AA battery, what DC volts is the multimeter showing?
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    • retiredcaps
      Badcaps Legend
      • Apr 2010
      • 9271

      #3
      Re: Repairing shunt in DVOM??

      5) A clear focused picture of the entire backside pcb would also help.
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      • modemhead
        Lurking
        • Jun 2012
        • 52
        • USA

        #4
        Re: Repairing shunt in DVOM??

        Your pictures are blurry. If you're talking about the solder, it was added to decrease the shunt's resistance. Sometimes it is nicked or crimped to increase the resistance. This is done to improve the accuracy of the high-current range.

        Originally posted by retiredcaps
        2) To measure volts and ohms, the current shunt is not used at all. Do not replace the shunt with a copper wire.
        Absolutely, positively, what he said.

        Comment

        • retiredcaps
          Badcaps Legend
          • Apr 2010
          • 9271

          #5
          Re: Repairing shunt in DVOM??

          6) Did you have an oops moment? Like trying to measure mains AC with the dial set on resistance?
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