Number of data points recorded decreases with time

[rohan_koka]

Hi, 

I have a VI which I use to control, visualize and save measurement data. I use drivers from Agilent 34401 and Agilent N6700 Series to control the pump and the heater. I also use a DAQ assistant to measure and visualize data. The problem I am having is that the number of data points visualized (in LabVIEW) and saved in the (excel sheet) decreases as the time increases even though the time is kept constant (for eg. 1800 sec for each power input). Attaching the VI along with the data from the excel sheet showing the decreasing number of data points with time below.

Any help will be greatly appreciated. Thank you.

[santo_13]

The biggest red flag is that you capture data and write to file in the same loop. The issue is that over time, the file size keeps on getting bigger and bigger, slowing down the loop.

The second red flag is the use of DAQ Assistant, it may be functioning in a short time, but will not take you far. It is best to learn DAQmx drivers and use them.

The third red flag is the use of Dynamic Data Type, I would avoid them completely.

[rohan_koka]

Thanks for the suggestion. I am new to LabVIEW programming, I will try to clean up the VI and see if that helps.