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how to get stable values?

I am using DAQ to measure pressure and level.

But these values are fluctuating even though I have done proper connections and grounding.

Also I added averaging for the Nchannel 1data configure.

Please let me know which is best solution to avoid the unstable values.

 

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What is the needed update rate?

Simple said, stable values are just a question of enough averaging 🙂

BUT if you sample with a rate close to the line frequency (without alias filter)  you can get even lower freq noise.

 

How does your signal look like with higher sample rates: Post a picture (png) of 600(0) points sampled at for 60ms ( would give 10(0)k sample rate) 

 

 

 

Greetings from Germany
Henrik

LV since v3.1

“ground” is a convenient fantasy

'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'


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This might not fit in this thread, but I got a DAQmx USB-6225. When I wanted to use it for measuring voltages I got a lot of noise on the signal. Especially with higher sampling rates. I could also see the sampling frquency as noise on the measured signal. If I tried to use multiple channels I got ghost frequencies from the first channel. To avoid this I had to measure over a resistor with a value below 1kohm. To get the best results I had to use a voltage follower with high input impedance and next to zero output impedance. I have never measured pressure and stuff, but if you measure over a resistor, you should concider what I explained here. It's also in the manual for the DAQ your are using.

Regards,
Even
_________________________________
Certified LabVIEW Associate Developer

Automated Test Developer
Topro AS
Norway
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