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LabVIEW
Sampling rate
You can sample at whatever rate you want. Generally you want to be sampling faster than your source, so just keep it at 1 kHz.
The sample rate is how fast the DAQ device records the input voltage. The low-pass rate is the fastest sine wave that will be transmitted through the amplifier. Though both are in Hz you can't directly compare the two.
If you sample a 53 Hz sine wave at 53 Hz you'll just see a row of constant points! If you want to see a nice smooth sine wave, sample at 10x or 100x the wave frequency. At 1000 Hz sample rate, you'll get 18 points per wave, which should be plenty.
Hi Yum,
@Pukhtun_Yum wrote:
And what about the number of samples ? If input analogue signal peaks at 53 Hz and the sampling rate of DAQ is 1k Hz then how much should be the number of samples ?
You define number of samples according to your requirements!
There is a simple formula describing the relationship: time * samplerate = NumOfSamples
(For continuous reading I advise to read 1/10 the samplerate, so at 1kS/s I would read 100 samples per iteration...)
@Pukhtun_Yum wrote:
What if the number of samples are greater than sampling rate ? How would it effect the measurement ?
Like for example if sampling rate is 1000 and number of samples are 2500
2500 Samples) / (1000 Samples/second) = 2.5 seconds
So it will take 2.5 seconds to take that data.
