Voltmeter on the fritz

Discussion in 'Tools and Fabrication' started by lowtops, Feb 20, 2009.

  1. lowtops

    lowtops

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    I have a Craftsmen digital voltmeter. I was testing the spark plug wires/coil on an old motorcycle I have and I think I screwed it up.
    I connected the positive lead to the spark plug wire and grounded to the engine case. Hit the starter and the display went haywire and then blank. I checked and replaced the fuse, put in a new battery and still nothing.
    I discussed this with my neighbor and he told me you cannot test "pulsing" power sources with a digital voltmeter, you have to use an analog.

    Is this correct?
    Is my voltmeter toast?
     
  2. CruisenSurfin

    CruisenSurfin

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    Well, you probably overloaded the internal circuits of the voltmeter. Most voltmeters can't handle that high of a voltage that is being produced at the spark plug.

    Jesse
     
  3. FJ40_owner

    FJ40_owner

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    x2

    The high voltage may have fried the display or some such circuits.

    Next time buy a Fluke. I overload them all the time and they keep working.
     
  4. Dirtsquirt

    Dirtsquirt

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    Bummer

    That is like 20k volts + no multimeter will stand up to that unless it has a high tension lead attachment. When i say no multimeter I mean common meter. like a Fluke 77 fluke 23 etc.
    If you are lucky the fuse inside will blow on the fluke. I have seen it blown by peeps checking voltag with em set on ohms.
     
  5. fj40forlife

    fj40forlife

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    I think its the fluke 87. Really fast reading. Thats what I use
     
  6. dfmorse

    dfmorse

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    Ah yes; 20k volts. Really wakes u up. Will also fry internal diodes and chips of voltmeters that are not eqpt with high voltage test leads.

    U now have a gadget that can be used for target practice...
     
  7. lowtops

    lowtops

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    Thanks guys, guess I'm in the market for a voltmeter.
     
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