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Set Dynamic Data Attributes interferes with Write to Measurement file Time column

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I recently got LabView 2016, I have hit a issue that I can not resolve on my own.

 

In essence I have a Measurment Computing 16 channel single ended DaQ and I am using it to measure temperatures from 10K thermistors. The program works by taking a 5volt reference signal and Stienhart-Hart 4 coeficiant equation to calculate tempereature. The program samples these once a sec in a while loop and then get moved to a shift register so that i can calculate a moving average for the thermistor measurments.

 

I then have a seperate While loop where I have local varibles for the calculated moving averages that go to a merge signals then to a Write to Measurment VI(formatting to Microsoft Exel) once a minute. This all works great and is super accurate.

 

The problem occures when I go to name each channel with the Set Daynamic Data Attributes, I plug the Vi to the channels and select checkbox by signal name. I create a control for this so that the user may rename each channel based on its senor location. The name appears in the correct column but when doing this the Write to Measurment Vi does not record absolute time correctly, it will record the very first collection but after it defaults to Jan 01 1904? and when I remove the Set Daynamic Data Attributes it continues to work properly. Having the the channels named would be a great addition for my Front panel. Any suggestions?

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Here is a snap shot of my program running.

 

There are seven 10k thermistors hooked up and placed in a cup of water. The max thermistor error from the manufacture is 0.2C

Just need the Set Dynamic Data Attributes to not interfere with the Write to Measurement time column.

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Hi,

 

Are you naming the channels while the program is running? Or do you complete this before clicking the Run Arrow?

 

Is this running on a RTOS? E.g. CompactRIO. Sometimes odd things happen with timestamps on RTOS, so I want to eliminate this as a possible source of error. We have one or two KnowledgeBase articles floating around about it.

Andrew T.
"His job is to shed light, and not to master" - Robert Hunter
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Hello and thank you for the response

 

I am entering the names prior to starting the program. 

 

Also i am not using a RIO, I am using an MC USB-1608g device.

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Solution
Accepted by topic author sdzr-css

Hi,

 

If you're trying to get timestamp data, I would recommend using the Get Date/Time in Seconds and the Get Date/Time String functions. You can find them under the Functions >> Timing palette.

 

The Set Dynamic Data Attributes express VI can give you timestamps, but these functions will be much more reliable.

 

Get Date/Time in Seconds

https://zone.ni.com/reference/en-XX/help/371361H-01/glang/get_date_time_in_seconds/

 

Get Date/Time String

https://zone.ni.com/reference/en-XX/help/371361J-01/glang/get_date_time_string/

Jorr-El
Robotic Systems and Controls Engineer
Simplifying Automation With Industrial Robots
Certified TestStand Architect
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Thank you for your help this was a perfect solution 

 

Feeding the Set Dynamic Data Attributes with the Get date/time vi has fixed the issue with the time columIt is now being recorded properly.

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