Question about measuring current with Fluke 287

Discussion in 'Test & Measurement Forum' started by nbenm, Oct 9, 2017.

  1. nbenm

    Thread Starter New Member

    Oct 9, 2017
    1
    0
    Hi,

    I need to measure current on a board.
    This board is running during ~ 6 seconds and sleeps during 10 minutes.
    Current while awake is ~ 200 mA, and ~ 17 µA while sleeping.
    The manual tells to set the rotary switch to "µA" for currents below 5000 μA (5mA), and to A/mA for currents above 5000 μA.
    As I have the two during the time of measure, what would be a good way to do this ?

    Thanks for your advice.
     
  2. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Set to microamps and measure current at startup (low current mode).

    Set to milliamperes and restart the device, then wait for it to switch to high current state.
     
  3. kubeek

    Expert

    Sep 20, 2005
    5,518
    1,062
    Or, you can set your meter to uA, but short the two plugs on your meter with another wire and wait until the device goes to sleep. Then undo the short and measure the low current.
     
    GopherT likes this.
  4. KeepItSimpleStupid

    AAC Fanatic!

    Mar 4, 2014
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    Meter resistance may impact measurements.
     
    dl324 likes this.
  5. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    True for all ammeters. At 17 microamps, that is about 60,000 ohms per volt. The internal resistance of the ammeter shouldn't be a major issue unless the OP needs 4-digits of accuracy.
     
  6. KeepItSimpleStupid

    AAC Fanatic!

    Mar 4, 2014
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    GopherT likes this.
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