I set up a circuit to give me a current flow of 450uA, i measured this with a 6000 count DMM and no problem, then i measured it with a 19,999 count DMM and i didn't have enough decimal places to get a reading, the 19,999 count DMM (Finirsi 2c53t) is fully auto where as the PM18 DMM is fully manual.

I was under the impression that the higher the DMM count is that the higher resolution can be obtained?

 

I set up a circuit to give me a current flow of 450uA, i measured this with a 6000 count DMM and no problem, then i measured it with a 19,999 count DMM and i didn't have enough decimal places to get a reading, the 19,999 count DMM (Finirsi 2c53t) is fully auto where as the PM18 DMM is fully manual.

I was under the impression that the higher the DMM count is that the higher resolution can be obtained?

Higher resolution means just that -- the reading has a higher resolution (than a lower-resolution meter).

Resolution is unrelated to sensitivity.

For instance, say I made a one-million count meter with a full-scale reading of 10,000 V. The resolution would be 100 mV (which may or may not be a good match for it's true sensitivity, but certainly it couldn't respond to 10 mV changes). Now I make a 1000 count meter with a full-scale reading of 100 mV. It's resolution would be 10 µV (and, again, that may or may not reflect it's true sensitivity).

I took a quick look at the Finirsi specs and it's most sensitive current range is 19.999 mA, which means it's resolution on that scale should be 1 µA. Unless there is something about your circuit that is causing it to bounce around between ranges, you should get a pretty good reading on 450 µA.

You had another thread where you were talking about 450 nA. Please confirm what the current level is that you are actually trying to measure.

What is the make and model of the 6000 count DMM you are using? What range are you setting it on?

For example, the OWON OW18B is a 6000 count DMM with a 60 µA range, giving it a 10 nA resolution.

 

What is the minimum current sensitivity range of each meter?

 

What is the minimum current sensitivity range of each meter?

I don't know about the Fnirsi but the sensitivity of the PM18 i am using on 60uA range and that allows me to view what i need, i.e 240nA.

 

Higher resolution means just that -- the reading has a higher resolution (than a lower-resolution meter).



You had another thread where you were talking about 450 nA. Please confirm what the current level is that you are actually trying to measure.

What is the make and model of the 6000 count DMM you are using? What range are you setting it on?

For example, the OWON OW18B is a 6000 count DMM with a 60 µA range, giving it a 10 nA resolution.

Yes i am trying to measure 450 nA i am setting the 6000 count DMM on 60uA range, the make and model is mentioned in my initial post.

 

that is 1000x smaller value (nano vs micro).
450nA=0.45uA=0.00045mA
so if the meter has most sensitive range 19.999mA,
the smallest non-zero value that can be displayed is 0.001mA
but the value you wish to see is 0.00045mA and of course it will be displayed as zero

btw, only handful of DMMs have low uA range.

 

that is 1000x smaller value (nano vs micro).
450nA=0.45uA=0.00045mA
so if the meter has most sensitive range 19.999mA,
the smallest non-zero value that can be displayed is 0.001mA
but the value you wish to see is 0.00045mA and of course it will be displayed as zero

btw, only handful of DMMs have low uA range.

Thankyou Panic mode, thats what i needed to know.