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Error -200019 by data acquisition of 3 channels (no external clock)

Hello, I have a question and hopefully somebody can answer it.
Technical details:   Labview 7.1, PCI 6220 and a/d converter BNC-2111

Problem:
I made a continous data acquisition with 3 physical channels. The problem is in choosing the sample rate. At a rate over 84000 Hz there is the Error
"-200019" and I don´t understand why. Is it a hardware problem or a software problem?
 I dont think it´s a software problem because the example works fine with a rate under 84000 Hz. Then if I choose 2 physical channels i can use a higher rate (over 120000Hz) but the same problem happens at a special rate.
Maybe the hardware is not good enough? What can it be? We want a data acquisition of 3 channels with a rate of 100000 Hz.

And of course I read some examples in the discussion forum but they don´t helped me. And no i don´t use an external clock. ;D

Thank you for answer my question.
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The reason for the error message is simple: you succeed the overall sampling rate of the device.
The 6220 has an overall samplingrate of 250kS/s. So acquiring more than one channel reduces the samplerate per channel. The maximum samplerate per channel is

overall samplerate / # channels.

So in your example:
250kS/s / 3 = 83.333 kS/s

And because 84 kS/s > 83.333 kS/s, you will get the error.....

hope this helps,
Norbert
Norbert
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CEO: What exactly is stopping us from doing this?
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@Anni wrote:

Maybe the hardware is not good enough? What can it be? We want a data acquisition of 3 channels with a rate of 100000 Hz.



To extend my answer in regard of this question: Yes, the hardware "is not good enough" in this case. The restricition i explained is true for all devices which multiplex the signals to one ADC. The benefit of this technologie is a far cheaper proicing for those products.
To solve your requirements, you can now go for a multiplexing device (E- or M-Series) with a higher overall samplerate of minimum 300 kHz or switch to a synchronuous device like the S-Series. But S-Series are far more expensive.....

hope this helps,
Norbert
Norbert
----------------------------------------------------------------------------------------------------
CEO: What exactly is stopping us from doing this?
Expert: Geometry
Marketing Manager: Just ignore it.
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Wow. Thank you so much for your fast answer.
It helps me allot. Then I have to think about a better hardware component.
Best regards.


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