How can I speed up saving time for saving multiple real time traces?

[csd8514]

I have a 6024E daq card with a 1531 accelerometer card connected in the chassis. I currently have 4 accelerometers (one more coming soon) attached to the system. When I try to save the traces to an excel file, it takes anywhere up to 15-20 seconds for it to complete the save. Currently, it saves 8000 points per data line. Is there something I am doing wrong with the buffer size or is it going to take that long to save 4 traces that large?

[Michael_Munroe]

It sounds like you are using ActiveX to control Excel using the Example VIs as provided with LabVIEW. If this the case, please see this thread from one week ago:
http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=506500000008000000F67B0000&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0

If you are trying to write to a text file, try using the "Write to Spreadsheet" VI and wire your data as a single 2D array. This will write your data as a single disk access. My machine wrote 8000x5 DBL in 125ms.

Michael Munroe
Certified LabVIEW Developer
www.abcdefirm.com

[Dennis_Knutson]

ActiveX is not the speediest method to use. A faster way would be use Write to Spreadsheet File which creates a text file as either tab or comma separated data. Excel is capable of reading either. The fastest method is save the data as a binary file and export it later into Excel. Look at the examples called High Speed Data Logger and High Speed Data Reader for how to work with binary files. If you absolutely must write to an Excel file real-time, make sure you're not opening and closing Excel each time. Have Excel open before you start your acquisition, keep appending data to the same file or a different worksheet in the same file and close Excel at the end of the acquisition.