PXI-4072 Capacitance measurement error

[MicTek]

Hello everyone.

Is it possible to show not only the measured capacîtance value but also the range of uncertaintly of the specific measurement?

[ChristophersonJ]

Hi MicTek, 

The  'Uncertainty' of the measurement could be represented in terms of  the gain and offset error. 

This is shown in the specs for the device as (%of reading + % of range): http://www.ni.com/pdf/manuals/376167b.pdf#page=9

If you wanted to do this programmatically, you could implement a small LUT of the spec, read from the Range property as the reference point (% of Range), have the user implement their expected value (% of Reading), and do a little bit of math on the back end to display a measurement certainty range to the user. 

Here's a rough guide on how you could implement the math: 

http://zone.ni.com/reference/en-XX/help/370384V-01/dmm/accuracy/

Best Regards. 

ChristophersonJ

[MicTek]

Hi ChristophersonJ !

Thanks for your answer. The links were helpful. With that it is possible to calculate the accuracy according to the device specifications.

What I wondered is, if it is possible to extract a value for the accuracy of the specific measured capacitance value from the FFT peak analysis (e.g. the peak width) performed in background.