Hello all,
I have two 32 channel TC 2095 terminals which are connected to two SCXI 1102 B modules, which are connected to a PXI-6251 card within a PXI-SCXI-1050 chassis. I then use a PXI-8360 module and PCIe 8361 card to connect to my PC. I'm running Labview 2015 and have DAQmx 15.
When I try and acquire all 64 thermocouple above 650 Hz per channel, I get the warning message:
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Warning 200011 occurred at DAQmx Start Task.vi:7220001
Possible reason(s):
Clock rate specified is so high that it violates the settling time requirements for the acquisition.
Reduce the clock rate, or the accuracy of the measurement might be compromised.
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When I reduce the number of channels sampled or the sample rate, the error is no longer thrown.
I am trying to find where the bottle-neck is occuring in the system which causes the error message. At 650 Hz, 64 channels, the total sample rate is 42 kS/s (21 kS/s per SCXI-1102B module), which as far as I can tell is below the maximum sample rate of the SCXI 1102B (~ 50 kS/s for maximum 16 bit accuracy according to another thread), the PXI-6251 (1 MS/s aggregate for multiple channels), and the PXI-8360 (132 MBytes/s).
One other strange thing is that I have tried another M-series card - replacing the PXI-6251 with a nominally slower PXI-6221 (250 kS/s aggregate), but the maximum sample rate is still 650 Hz, which suggests to me that it isn't the M-series card but something else.
I am confused- any ideas where the bottleneck is occuring?
Many thanks,
Ben