Hello,
My application involves occasionally doing tests outdoors. We have a rugged PC and DAQ equipment. I'm in the northeast where the last few weeks were cold and we had to do a test outdoors. Long story short, in the middle of the test the computer shut down (most likely because it was too cold for the computer according to its spec sheet) and I lost all of the sensor data. The coomputer works fine BTW when I brought it back indoors.
The reason the data was lost was because the program never finished executing and thus the function that writes the data file did get a chance to run. Now, the DAQ card we used is very old and obsolete. I'm in the process of upgrading the hardware with NI components (PCI-6221) and an SCC-2345 box with load cell modules for two load cells. Along with that I am writing a LabVIEW application that improves upon the old, obsolete program.
I want the application to continuously write a spreadsheet file with all the sensor information as the test is occuring in case the computer fails midtest. That way, I at least have some data saved. I was explaining all this to another engineer here and he says that it can't be done that way at high sampling rates (I want to run the program at 1kHz for 60 seconds). His reason was that writing to a file will screw up the waveforms we are measuring because file has to be opened, the data gets written, and then closed again for each row of data points. He contends that the computer resources will be tied up as it tries to write the file while the program is acquiring data and keeping that data in a memory buffer.
So my question is: what's the recommended architecture to write a backup file as a test is occuring with a high sampling rate (1kHz to 10kHz) in case the computer shuts down or some other failure occurs? Also, what are the performance limitations when writing data to a file within the same loop as the "read" VI?
Thanks.
