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  1. #1
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    Different current measurmen numbers on a FLUKE 289

    I'm trying to figure out why when I measure current on my FLUKE 289 meter it reads .536 on the mA scale and 276 on the uA scale when I apply .52v from a power supply through a resistor. I assume the difference internal resistance. Can anyone confirm?

    Thanks

    PV

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  2. #2
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    Re: Different current measurmen numbers on a FLUKE 289

    Hi,

    What's the resistor value?
    Show a photo how you connected it.
    AC or DC?
    If AC: is the Voltmeter trueRMS or not? What waveform?

    970 ohms vs 1884 ohms ... this means a difference of more than 1000 ohms. Unusual.

    Klaus
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  3. #3
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    Re: Different current measurmen numbers on a FLUKE 289

    My meters are the same. Each mA range contains a different shunt resistance.

    When current level is unknown I start with the highest mA range to take a reading. If the meter moves a tiny distance upscale, then I switch to a lower range.

    - - - Updated - - -

    I continue this way until I get a usable reading.



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  4. #4
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    Re: Different current measurmen numbers on a FLUKE 289

    Hi,

    Last page of the datasheet tells the burden resistances in current measurement mode.
    It is 102 Ohms vs 1.8 Ohms ... does not explain your results.

    Can it be you overloaded the uA range input in the past ... and it is broken now?

    Klaus
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  5. #5
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    Re: Different current measurmen numbers on a FLUKE 289

    No I never did that but whenI measure current on a circuit with more resistance it's more accurate. I guess it's the internal resistance



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