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Logging data only when value of tag increases

Hello,

 

I want to data log only when my tag value is increases another it will not log data in database.

So how do I do this.

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Thanks & Regard
Nitin Jain
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A functional global, which will look at the current value, compare it to the previous, and if the new value is greater, signal that fact, and replace the previous value with the new value. You probably want the comparison to have a range, or a threshhold, so that it has to have increased by a certain amount before this all occurs, also are you only concerned in increasing? If you signal were a slow sinusoidal one you would register increases all the way up one side of the waveform, then once the peak was reached no more data would be saved, unless of course the amplitude increased. Do a search on functional globals, Action Engines, to see what I'm refering to as a storage mechanism.

Putnam
Certified LabVIEW Developer

Senior Test Engineer North Shore Technology, Inc.
Currently using LV 2012-LabVIEW 2018, RT8.5


LabVIEW Champion



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Hi,

Thanks to reply, could you please give me any example of functional global & Action Engines.

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Nitin Jain
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HI Nitin,

find the link for function global : http://zone.ni.com/devzone/cda/epd/p/id/3124

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this link do not have a example file.

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Thanks & Regard
Nitin Jain
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Hi,

In that link VIs are there in the zip attachment..Here i attched the same for you which saved in LV7.1

 

For details on FG : http://labviewwiki.org/Functional_Globals

 

Have a Happy New Year Smiley Happy

 

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