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Waveform chart

Friends,
I configured my waveform chart to display time in minutes and seconds on the x-axis. However, a number appears before the minutes and seconds, as shown in the figure. Is there any way to make the program not display this strange number? Thank you for your help!

MarceloPinto71_0-1721830872198.jpeg

MarceloPinto71_0-1721830968721.jpeg

 

 

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Message 1 of 20
(640 Views)

What are the time values? (e.g. how is t0 obtained) Could it be they are absolute (seconds since ~1904)  instead of relative?

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Message 2 of 20
(624 Views)

Time comes from elapsed time vi.

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Message 3 of 20
(606 Views)

Set start time (s) --> 0

 

MarceloPinto71_1-1721835082432.jpeg

 

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Message 4 of 20
(599 Views)

You need to be more specific. Can you explain how things are wired up, maybe attach a simplified version of your VI (save for previous, 2020 or below).

 

A chart does not accept an elapsed time anywhere. What is dt? What is the datatype (dynamic, waveform, array, scalar cluster, etc.). How is the x-axis configured?

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Message 5 of 20
(591 Views)

MarceloPinto71_0-1721838100372.jpeg

 

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Message 6 of 20
(581 Views)

It is a simple continuous voltage acquisition.

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Message 7 of 20
(580 Views)

63411218 minutes is about 120.6 years, which is about the same time between the "zero time" of LabVIEW (Jan 1 1904) to now.

 

Somewhere, somehow, you have converted a time stamp into a value that the waveform chart thinks is what it needs to display as the time counter.

 

You might want to consider using a "graph" instead of a "chart".  A chart seems easy because you only pass in the Y values and it takes care of X for you as well as storing all previous values in the chart until they roll off, but it comes at the cost that all the X values are evenly spaced and difficult to define.

 

With a graph you will need to both define the X,Y pairs more precisely and maintain your own copy of the complete data you want to show, but the increase in control over what you see is always worth it in my experience.  I haven't used a "chart" in any application larger than a single quick testing VI in years.

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Message 8 of 20
(578 Views)

Forgiveness! Elapsed time was used elsewhere in the code and has nothing to do with this specific case. In this case, it is simply a waveform chart showing the values ​​acquired over time.

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Message 9 of 20
(577 Views)

we cannot debug pictures.

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Message 10 of 20
(552 Views)