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Sample Rate with DMM-4081 (6,5 DIgits) is very low

Hello

In my application I do a AC Volt Measurement with a NI-DMM 4081 to measure values of a ECU between 30 µV and 100 µV.
I use Labview 2015 and latest DMM driver.

 

I attached 2 Screens of the ac configuration and the measurement VI.

DMM Config:
Range: -1 (Auto)
Digits: 6,5
Min Freq: 500Hz
Max Freq: 2kHz

 

Problem:
The Multi Point VI needs at least 6 seconds to acquire 10 Samples. That means a sample rate smaller than 1 S/s.
If I enable AutoZero and ADC it takes 60 seconds for 10 Samples.

Actually the goal is to add a lowpass filter behind the Multi Point VI. With this sample rate it's almost impossible to use a filter VI afterwards
because the filter VIs require a samplerate bigger than the cut-off frequency (500Hz).


I found this page http://www.ni.com/tutorial/6234/en/

According to this we can only reach a sample rate of 100 S/s with 6,5 Digits.
And yes I can see that AutoZero and ADC decreases the measurement speed if enabled.
But I didn't expect such a low sample rate of under 1 S/s.

 

Is there any possibility to improve the measurement speed? And to add a filter afterwards.

Thanks for any advice.

Greets

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@shavo wrote:

Is there any possibility to improve the measurement speed?


Sure.  Lower your resolution.

 

You are stuck in what every DMM and DAQ has to fight: accuracy vs speed.


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