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Author Topic: Do I need a resistor for each LED?  (Read 1813 times)
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Most modern DMM have both separate resistor shunt(s) and separate fuse(s) for typically the two different current jacks.

Lefty

I have two of the same Fluke (70-series) meter.  I cleared the fuse in one of them (the mA) and replaced it with an "equivalent" rated fuse.  Then the readings were off.  I swapped the fuse with the other which still had its original and it was better.  I placed the "equiv" in the other meter and then it was off.

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Most modern DMM have both separate resistor shunt(s) and separate fuse(s) for typically the two different current jacks.

Lefty

I have two of the same Fluke (70-series) meter.  I cleared the fuse in one of them (the mA) and replaced it with an "equivalent" rated fuse.  Then the readings were off.  I swapped the fuse with the other which still had its original and it was better.  I placed the "equiv" in the other meter and then it was off.



If you check your Fluke user's manual I suspect it says there are no 'equivalent' fuses for the meter and to only use fluke 'approved' fuses designed for the model in question. They are hellishly expensive also.

Lefty
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Sorry, I have a handful of meters with no current measurement. And before that, I had meters that had relatively high resistance on the lower current ranges. With 0.1 ohms (typo said 0.7 ohm) on the 200.0mV scale, I can measure down to 1mA.

Probably not an issue with newer DMMs with lower current shunt resistors.
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