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time measurement between counter output my device and analog input

Hello!

I'm trying to measure the time to generate a digital pulse train on the counter output, that goes to a frequency converter that controls a motor.  So I think it'd be the best way to wire the output of the frequency converter with an analogue input and make a timestamp before I generate the pulse and a timestamp when I recognize the singal, but I think that wouldn't be a serious measurement :)?

What's the best way to measure the time?

kind regards peter
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hi there

well, there a several ways to do this. the problem with the software - timestamps is the minimal resolution of 1ms. i'd suggest:

- wire a copy of the digital pulse train to an analog input channel
- wire a copy of the frequency converter to another analog input channel
- create an analog input task with the two channels (the sampling rate defines the timing resolution,make sure to acquire enough samples to see the response signal) 
- start this task
- send the digital pulse train

to optimize your acquisition you can use another copy of the digital pulse train as a start trigger for your analog acquisition.

-> then you'll see the digital pulse train on one of the analog channels and the frequency output on the other one. both channels have the same time axis with a resolution defined by your sampling rate (~us depending on your hardware). then you can analyze the data.

search the example finder for examples of how to create tasks and triggers.


 

 

Best regards
chris

CL(A)Dly bending G-Force with LabVIEW

famous last words: "oh my god, it is full of stars!"
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hey chris,

thank you for your reply, but I have decided to prefer the oscilloscope and do the measurement without labview! I think that's the easier way 😉

Kind regards Peter
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yeah, that's surely correct!

but make sure that the device is stable and that the delay dosn't depend from the pulse train.

Best regards
chris

CL(A)Dly bending G-Force with LabVIEW

famous last words: "oh my god, it is full of stars!"
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