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Labview program to read 8 thermocouples and 3 pressure transducers

I have a NI cDAQ -9174 with NI-9201 and NI-9213 modules. The labview programm I have can read 8 thermocouples and 3 pressure transducers. When I choose the configaration of the DAQ Assistant on Continiuos Samples, after a long running time (labview), Error 200279 pops out and stops the labview: error 200279 says "Attempted to read samples that are no longer available", increase in buffer size, reading the data more frequently or specifying a fixed number of samples to read instead of reading all available samples might correct the problem". I am attaching the picture of my labview. Please help me on this,  labview.JPG

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There is nothing to debug since you're only showing a picture of DAQ Assistants and Express VIs.  We have no idea how they're configured.  

 

In any case, for an intermittant issue like this you'll have to convert to real LabVIEW code with a proper state machine architecture and error handling.  The Express stuff is just for new users and quick code to do one-off jobs.  It isn't appropriate for a data logger.

 

State machine:  http://www.ni.com/tutorial/7595/en/

 

DAQmx:  http://www.ni.com/product-documentation/5434/en/  

                 http://www.ni.com/product-documentation/2835/en/

 

LabVIEW Pro Dev & Measurement Studio Pro (VS Pro) 2019 - Unfortunately now moving back to C#, .NET, Python due to forced change to subscription model by NI. 8^{
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SUJITHNITK a écrit :

I have a NI cDAQ -9174 with NI-9201 and NI-9213 modules. The labview programm I have can read 8 thermocouples and 3 pressure transducers. When I choose the configaration of the DAQ Assistant on Continiuos Samples, after a long running time (labview), Error 200279 pops out and stops the labview: error 200279 says "Attempted to read samples that are no longer available", increase in buffer size, reading the data more frequently or specifying a fixed number of samples to read instead of reading all available samples might correct the problem". I am attaching the picture of my labview. Please help me on this,  


Simple, you have to much going on in your loop. Either slow the acquisition rate or better use a Producer/Consumer Design Pattern (Data) where you enqueue the data in the producer loop and process it in the consumer queue. The Write to Measurement File express vi is the worst offender here, it realler is what slows everything. It is usually not a good practice to save to file in the same loop as the acquisition.

 

Check Fiule - new ... From Template - Frameworks - Design Patterns - Producer/Consumer Design Pattern (Data) to get you started.

 

Ben64

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