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Is Possible to get one sample data per one trigger pulse in NI 4472 ?

Dear All,

 

Iam using NI4472 for PCI card. In that i want only one data whenever i give the digital pulse in trigger input. This is possible?. If this is Possible then how to configure the setting to get the data from NI4472 card. Can Any one help me

 

 

Regards,

Vijay

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There are two options. 1 - digitize the trigger along with the analog and use LabVIEW to pick out the analog value from your acquisition when the trigger pulse is seen in the other channel. In this way, you perform continious acquisitio with the NI 4472. This is a basic decimation technique. 2 - use the Sound and Vibration Measurement Suite functions of order analysis to analyze the trigger pulses to identify the reference (angular position of a shaft for example) and then re-sample the data with the resampling functions to line up the data with the reference. In this way, you can have more than one data point per trigger, evenly spaced between the triggers. http://sine.ni.com/nips/cds/view/p/lang/en/nid/203624
Preston Johnson
Solutions Manager, Industrial IoT: Condition Monitoring and Predictive Analytics
cbt
512 431 2371
preston.johnson@cbtechinc
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Thanks for your reply,

 

In that first options How to configure the digital pulse in external clock? Any setting procedure is there? Can you give the details about first options.

 

Thanks in advance

Regards,

Vijay

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Can you simply wire the digital pulse into an analog channel and then sample both the analog and the digital at say 100kSa/second.  View these on an graph and you can then see the relationship. 

 

You can use a peak detector on the digital pulse channel to find the index where it occurs and pull the analog value from the vibration channel out of the other array. 

 

 

Preston Johnson
Solutions Manager, Industrial IoT: Condition Monitoring and Predictive Analytics
cbt
512 431 2371
preston.johnson@cbtechinc
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Thanks for your reply,

 

Now that is working, But problem is i need to use external trigger input to give digital pulse, not any one of analog input channel for digital pulse. Because i need to extra coding to detect the peak pulse values and extract the index values from analog input array. If EXT trigger input is used i can avoid extra coding and execution timing.For that can you give some details.

 

Thanks in advance,

Regards,

Vijay

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Can you help me to solve this problem.

 

Regards,

Vasu

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The digital input line is only a start trigger on the 4472.  It will start the acquisition process, then it is free running. 

 

Our Sound and Vibration measurement Suite has the functions for aligning your data to a reference clock, such as an encoder pulse from a rotating shaft.  You can download an evaluation copy from our web page

http://sine.ni.com/nips/nisearchservlet?nistype=psrelcon&nid=203624&lang=US&q=FQL:%28locale%3Aen%29+...

 

You can then use the tacho and resampling functions to get data aligned with any number of points per reference. 

 

The alternative is to work on the coding as I have suggested

 

 

 

Preston Johnson
Solutions Manager, Industrial IoT: Condition Monitoring and Predictive Analytics
cbt
512 431 2371
preston.johnson@cbtechinc
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