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Dave Tweed
Dave Tweed
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I have asked here a month ago regarding measurement of very low current. I was told that Amper-Meters today has this resistance in series that will cause a voltage dropoutdrop, hence you can't measure a very low current.

So what happened with my flukeFluke is a very strange thing. If I put it on the scale of 2mA, or even 20mA, and try to measure current in my PCB, I get many resets of the mcuMCU because the voltage is droppeddropping.

But I discovered something else, if I put the scale on the Ampere meter to be in 20A  ,than then the pcbPCB is working and I can measure the current (!).

So my questions are:

  1. Why is it working only with a scale of 20A ?

  2. Are the measurements good? canCan you count on them? I can tell that the LCD shows a curent of 0.03 in this scale, that means its about 30uA? (that's what I expect)

I have asked here a month ago regarding measurement of very low current. I was told that Amper-Meters today has this resistance in series that will cause a voltage dropout, hence you can't measure a very low current.

So what happened with my fluke is a very strange thing. If I put it on the scale of 2mA, or even 20mA, and try to measure current in my PCB, I get many resets of the mcu because the voltage is dropped.

But I discovered something else, if I put the scale on the Ampere meter to be in 20A  ,than the pcb is working and I can measure the current (!).

So my questions are:

  1. Why is it working only with a scale of 20A ?

  2. Are the measurements good? can you count on them? I can tell that the LCD shows a curent of 0.03 in this scale, that means its about 30uA? (that's what I expect)

I have asked here a month ago regarding measurement of very low current. I was told that Amper-Meters today has this resistance in series that will cause a voltage drop, hence you can't measure a very low current.

So what happened with my Fluke is a very strange thing. If I put it on the scale of 2mA, or even 20mA, and try to measure current in my PCB, I get many resets of the MCU because the voltage is dropping.

But I discovered something else, if I put the scale on the Ampere meter to be in 20A, then the PCB is working and I can measure the current (!).

So my questions are:

  1. Why is it working only with a scale of 20A ?

  2. Are the measurements good? Can you count on them? I can tell that the LCD shows a curent of 0.03 in this scale, that means its about 30uA? (that's what I expect)

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edit approved Jul 25, 2015 at 11:56
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edit approved Jul 25, 2015 at 11:56
On the way to success
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I have asked here a month ago regarding measurement of very low current  . I was told that Amper-Meters today has this resistance in series that will cause a voltage dropout  ,hence hence you cantcan't measure a very low current  .

So whats happenswhat happened with my flukfluke is a very strange thing  . if iIf I put it on the scale of 2mA, or even 20mA, and try to measure current in my pcbPCB, iI get many resets of the mcu because the voltage is dropped  .

But iI discovered something else,if i if I put the scale on the AmpermeterAmpere meter to be in 20A , thanthan the pcb is working and iI can measure the current (!).

 

So my questions are  :

  1. Why is it working only with a scale of 20A ?

    Why is it working only with a scale of 20A ?

  2. are the measurements good? can you count on them ? i can tell that the LCD shows a current of 0.03 in this scale, that means its about 30uA ? (thats what i expect)

    Are the measurements good? can you count on them? I can tell that the LCD shows a curent of 0.03 in this scale, that means its about 30uA? (that's what I expect)

I have asked here a month ago regarding measurement of very low current  . I was told that Amper-Meters today has this resistance in series that will cause a voltage dropout  ,hence you cant measure a very low current  .

So whats happens with my fluk is a very strange thing  . if i put it on the scale of 2mA, or even 20mA, and try to measure current in my pcb, i get many resets of the mcu because the voltage is dropped  .

But i discovered something else,if i put the scale on the Ampermeter to be in 20A , than the pcb is working and i can measure the current (!).

So my questions are  :

  1. Why is it working only with a scale of 20A ?
  2. are the measurements good? can you count on them ? i can tell that the LCD shows a current of 0.03 in this scale, that means its about 30uA ? (thats what i expect)

I have asked here a month ago regarding measurement of very low current. I was told that Amper-Meters today has this resistance in series that will cause a voltage dropout, hence you can't measure a very low current.

So what happened with my fluke is a very strange thing. If I put it on the scale of 2mA, or even 20mA, and try to measure current in my PCB, I get many resets of the mcu because the voltage is dropped.

But I discovered something else, if I put the scale on the Ampere meter to be in 20A ,than the pcb is working and I can measure the current (!).

 

So my questions are:

  1. Why is it working only with a scale of 20A ?

  2. Are the measurements good? can you count on them? I can tell that the LCD shows a curent of 0.03 in this scale, that means its about 30uA? (that's what I expect)

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Curnelious
Curnelious
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Measuring very low current

I have asked here a month ago regarding measurement of very low current . I was told that Amper-Meters today has this resistance in series that will cause a voltage dropout ,hence you cant measure a very low current .

So whats happens with my fluk is a very strange thing . if i put it on the scale of 2mA, or even 20mA, and try to measure current in my pcb, i get many resets of the mcu because the voltage is dropped .

But i discovered something else,if i put the scale on the Ampermeter to be in 20A , than the pcb is working and i can measure the current (!).

So my questions are :

  1. Why is it working only with a scale of 20A ?
  2. are the measurements good? can you count on them ? i can tell that the LCD shows a current of 0.03 in this scale, that means its about 30uA ? (thats what i expect)