Isolating Current Spikes

[Mmoon]

Hello,

I currently am attempting to use DIAdem to process a TDMS file that has voltage and current data. My goal is find specific spikes in my voltage data that indicate when a display is turned on (this is indicated by a -30 to -80 mA spike). I am new to DIAdem and have been having a hard time figuring this out. Does anyone have possible solutions?

Thanks

Mmoon

[Otmar]

Hello Mmoon,

There are multiple ways dto do this.

A manual way would be to use the VIEW panel, and then highlight each spike manually using band cursors.

Another way is to use the "Find Event" (blue quare) feature in the ANALYSIS panel, or the "Find Peaks" (green square) function:

I'm happy to show you how to use these function using a WebEx web screen sharing session if we can set up a meeting between 9 am and 4 pm CDT (US Central Daylight Time). I can be reached at otmar DOT foehner AT ni DOT com - I can also recommend the online training tools at http://www.ni.com/white-paper/14598/en/

Best regards,

    Otmar

[Mmoon]

I actually wrote an incorrect description, I would like to see when my current data spikes to the values I specified in my previous note. I have tried using both find peaks and find events to attempt to isolate these peaks but have had no luck

[Otmar]

MMoon,

Can you share some data? Feel free to send it to the email address I left in my previous post ...

     Otmar

[Mmoon]

Here is an example data file. I have made some progress in picking the peaks out using event search but I would like to have you opinion on how to best analyze my files to find the current spikes. Please let me know what you think.

thanks,

Mmoon

[Mmoon]

Hi Otmar, Is there any chance that you had some time to look at the file I sent/may have some input into how I could process these files the way I want to?

Thanks

Mmoon

[Brad_Turpin]

Hi Mmoon,

Your Current channel has a number of vertical level shifts in it that make spike detection thresholding difficult.  For instance, between 171.4 and 173.3 on the X axis, the level shifts from an average value of 0 to an average value of -50, then to an average value of -20, then to an average value of -10.  How many events would you say are occurring in that X range?

Brad Turpin

DIAdem Product Support Engineer

National Instruments