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Calculate Delta X for Cycle Event

In reference to the attached .jpg, I am interested in determining the delta time from when “Aliases\OUTPUTS\CHOPPER_ENGAGE” [turquoise waveform] switches from 1 to 0 [BLACK arrow] and “[2]/Targets\cRIO9081-150HP\Hardware\Chassis\NI-XNET\CAN\AF9230\Incoming\Single-Point\UCM1_STATUS10 (419389568)\SpreaderSpeed” [violet waveform] reaches 0 [RED arrow]. 

 

The performed operation occurs in 3000 cycles so I would like this analyzed for each cycle. 

 

What would be most helpful is a 3000 row table [row for each cycle] with the following columns that I could analyze in Excel:

 

  • Column 1:  [1]/Targets\cRIO9081-150HP\User Channels\Counters\CycleCounter_Ctr
  • Column 2:  System or Absolute Time when CHOPPER_ENGAGE switches from 1 to 0
  • Column 3:  System or Absolute Time when SpreaderSpeed reaches 0

We started and stopped the test a few times so I have approximately [10] files to analyze but I can copy the table output to Excel each time I perform the calculation. [The attached file is the smallest data file I have with only one cycle iteration]

 

Any suggestions as to how to approach this?  

 

Thank you very much.

 

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New post as my original post was a reply to a "solved" topic [https://forums.ni.com/t5/DIAdem/Determining-time-at-a-given-channel-value/m-p/3881846#M25852]

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Hey Atarman,

 

I looked at Maura's post, and it seemed like what she suggested would be a good starting point. Was there something confusing about her suggestion or a misunderstanding?

 

Including Maura's suggestions for reference:

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As a good place to start:

  1.  Create a "Delta Time" channel that shows the time elapsed between each point, using the ChnDeltaCalc() command
  2. Some initial thoughts that I had were to utilize something like this function to determine when the value goes to 1 or zero:
    1. https://forums.ni.com/t5/DIAdem/Finding-Time-When-Waveform-Passes-Set-Threshold/td-p/3328849
    2. https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z000000P6u6SAC&l=en-US
  1. Then you can use the difference between where the points hit zero and one to calculate dt

It sounds like this will be similar to what was done on this post which may provide some insight: https://forums.ni.com/t5/DIAdem/Formula-for-finding-channel-value/td-p/1234321

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Bill B.
Applications Engineering
National Instruments
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