I use waveform chart VI to plot the setpoint as a g

reen line, process variable value in a white line, maximum and minimum in red lines.Is there a way that I can change the process variable color only for those points when the values are out of max and min range and leave the in range points still in white?The reason for doing this is to alarm the conditions when the process variable is out of limits. But we prefer not to change the color for the points when they are in limits.

reen line, process variable value in a white line, maximum and minimum in red lines.Is there a way that I can change the process variable color only for those points when the values are out of max and min range and leave the in range points still in white?Alberto,
Thank you for your VI. It triggered my mind. Now I can use three different plots to represent three different zones, then the color will change.
Great idea! It will work. since I have to use auto scale y, then I changed your VI, now you can auto scale y without seeing the NaN points. see attached VI.
I have the following questions:
1. how to clear XY chart using a front panel button?, seems no attribute for this.
Attachments:
colored_chart1.vi ‏41 KB

Similar Messages

Using waveform chart to collect data

Hello,
I am a new user to labview, however I have been using it for a while now.
I have a simple problem.
My model runs a drive cycle for 1400 secs.
I want to record data for a sample rate of 1 sec.
However, When I try to run the model and export it to excel it shows data for a sample rate of 0.1 seconds. How can I change that?
Also, what can be the maximum buffer size of the waveform chart?

Hey govindgoal,
The max buffer size is pretty massive so don't worry about that. I would post your code or at least the part which is recording the data for people to help debug. It would seem however that you have some timing issues with your application.
Regards
Andy
"To 'G' and not to 'C', this is not a question!"

Any alternate solution to using Waveform Chart Property Nodes 'ActPlot', 'Plot.Visible' for mulit-plot color problem on PDA?

Hello,
    On a waveform chart, 4 signals need to be plotted based on the status of 4 boolean inputs. Eg. if the first boolean input is true, the first signal needs
to be visible on the waveform chart; if the first boolean input is false, the first signal should not be visible on the waveform chart and so on. This can be
done on LabVIEW desktop using the Waveform Chart Property Nodes 'ActPlot', 'Plot.Visible' - a sample VI "BundleSignals_Select_Desktop.vi" is attached for
reference.
    But on PDA, since the Waveform Chart Property Nodes 'ActPlot', 'Plot.Visible' are not supported, some other method has to be used. I have done the
selection/de-selection of these signals using 'Insert', 'Delete' array functions as shown in the attached VIs "BundleSignals_PDA.zip" which works, but the
problem is that the colour of these signals do not work as desired when the selection/de-selection of these signals is done - It is required that the first
signal should always appear in White color, the second signal should always appear in Red color, the third always in Green color & the fourth always in Blue
color.
    I hope i have made myself clear of the problem. Has anyone faced this problem before & is there a solution?
Note: Version of LabVIEW that we are using: LabVIEW 8.5 Professional Development System for Windows Vista/XP/2000 and LabVIEW 8.5 PDA Module for Windows
Mobile.
Thanks & Regards,
Subhashini
Attachments:
BundleSignals_Select_Desktop1.vi ‏25 KB
BundleSignals_PDA.zip ‏26 KB

Unfortunately the only alternative to using property nodes is to set the properties manually on the development environement. The limited size of memory does limit us in terms of features for the module.
Mehak D.

Plotting data with multiple y-axis using waveform chart

I am using LabVIEW 7.1 and am simply trying to split my data on one waveform chart using 2 Y axis. One goes from 0-150 and the other from 800-1000. I want them to graph on the same chart, and I have selected 'duplicate scale' when I right click on the chart, as instructed in the labview manual, but both of my data streams are still only connected to one of my axis. I can't get it to recognize that one data stream should go on one axis and the other stream should go on the other axis. Can someone help please?

Right-click in the plot legend one plot. In the context menu select y-axis and after the axis you want for this plot. The scale is changed directly.
There is an image of the context menu attached.
I hope this helps
Greetings
shb
Attachments:
two y-axis.png ‏16 KB

Using Waveform Chart, inconsistent results when setting X range and delta X properties

I have isolated my problem to a simple vi consisting of only a waveform chart (attached). I am using LV 5.1.1. I have used an attribute node to set x minimum to 0, x maximum to 10, delta x to be entered by the user, and have turned autoscaling off.
When I plot 2 random points, x maximum is inconsistent, and doesn't stay at 10 when the vi is run several times in a row. Specifically, the first time the vi is run (after delta x is changed), x maximum changes. Then, the second time it is run, the max typically goes back to 10. However, when run several times in a row, x max will fluctuate. Specifically, I tried entering a delta x of 8. Mostly, the min is 0, max is 10,
and the line between the 2 random points plots from 0 to 8 along the x axis (good). However, every once in a while, the x max will go to 8.
This behavior is very strange, and will not allow me to program my actual application correctly until I fully understand what is happening. I would assume since Waveform Chart has these attributes to set, I can still using the Waveform Chart, and don't have to completely restructure my program to use another display.
Attachments:
deltaX2.vi ‏28 KB

That is the expected behavior, it is only that you don't assign the properties in the right order. If you set the XScale.Multipler before min and max all is how you expect it. When you set the multiplier, min and max are automatically changed to reflect the scale changes thus overwriting your previous settings.
LabVIEW, C'est LabVIEW

How to use waveform chart for slow data

For slow data acquisition (e.g. 1 sample / sec) in the case of using DMM, how to display those data in a chart / graph?
For this sampling rate, there will be only 1 point in the chart.
How to buffer them and display them in a sequence?
Or, any other method?
thanks

Here is a quick example showing chart, graph and XY graph. All YOU need to do is use a chart and wire your DMM reading right to it. Charts have their own built in history (you can change the buffer size by right-clicking > Chart History Length)
For more info see the Examples... Building User Interfaces > Displaying Data > Graphs and Charts
Using LabVIEW: 7.1.1, 8.5.1 & 2013
Attachments:
MultiGraphs.vi ‏17 KB

How do I update a waveform chart with multiple plots one point at a time?

Hi,
I am updating multiple plots one point at a time. That is, every time I update the chart I have a value for one of the plots. If I put in a cluster with NaN for each of the charts except the one with the data I can only get individual points on the chart. I would rather have them connected.
Any clues? The only thing I can think of is to delay the update and do interpolation between samples - too complicated for me.
Thanks

Are the points within a given plot equally spaced in time? If so, perhaps you need to maintain your own history of the data and used a waveform graph rewriting the history data to the graph each time. If the points are unequally spaced, then you will need to do it as an XY graph.

Waveform chart time axis is not matching the waveform data

So here an interesting conundrum I hope you might be able to help me with...
My VI has waveform data sent to a chart, though the data is not being plotted against the current time. Rather, it is being plotted starting way back in the reference time (way back in 1903). I don't understand why this is happening. When I build the waveform, I use the "Get Date/Time in Seconds" function outside the while loop and feed that into my "Build Waveform" Function as the t0 value. My dt value is 0.05 (20 Hz) and then I feed in my array of data in the Y input. Any ideas why the chart is plotting this data over 100 years ago? Thanks!
Andrew

Hiii, Ronin
Here is your solution.
By default, waveform charts and graphs display the absolute time at time 0 as 7:00:00 PM, 12/31/1903 on a Windows based system. Property nodes can be used to get the correct absolute time to display on the x-axis of the waveform chart.
First, right click the chart on the front panel and select X Scale >> Formatting. Then set the format to Absolute Time.
Create a property node for the waveform chart by right-clicking on the chart on the block diagram and selecting Create >> Property Node. Expand the property node to display two properties. Select the Format property and the Offset property. The Format property is located under X-Scale >> Format and Precision >> Format, and the Offset property can be found under X-Scale >> Offset and Multiplier >> Offset. Right click on the property node and select Change All to Write.
For the Format property, the context help shows that there are multiple inputs to this property. Wire in a value of 7 to set the format to Time and Date.For the Offset property, first wire the output of the Get Data/Time in Seconds VI to the input of the To Double Precision Float VI. Then wire the output of the To Double Precision Float VI to the Offset property.
In addition, if you know the number of data points plotted to the chart per second, you can set the Multiplier property located under X-Scale >> Offset and Multiplier >> Multiplier. If there are x data points generated per second, wire in a value of 1/x to the Multiplier property. A simple example program "Chart with Timestamp" that demonstrates how to do that is attached.
Thanks,
Nishant
Attachments:
Chart with Timestamp.vi ‏36 KB

Why does AI Read(Asynchronous).vi cause the waveform chart to not display any history ?

I trying to create a strip chart for 16 channels that will require displaying 10-20 minutes of data.It also starts a separate vi to set gains and offsets while displaying the data. Using AI Read.vi uses 100% of the CPU so the second vi does not run. But using AI Read (async).vi allows the second vi to run, but causes the waveform chart to not display the history? I'm using LabView version 6.0.2.

Hi Waynes World,
I have a couple of questions that may help us solve this issue...
1) If you are modifying one of our example programs, which one did you start with?
2) What kind of analog input are you doing? Buffered? Finite or continuous?
3) Have you tried increasing the buffer size of the strip chart? This will allow the chart to store more data in it.
4) When you use the Async VI, and when you are using the other, can you describe how the strip chart is showing the data... does the data in the chart keep growing and growing... or does it clear itself and start over when the pine reaches the end?
I think this issue is rooted in how the buffer is being used with the two different AI Reads and how it returns data to the chart.
On a side note, have you considered upgrading to a newer version of LabVIEW? Our latest versions of LabVIEW come with many new features and it is signifigantly easier to use.

Why does Waveform Chart Initalized by Property nodes behave erratically when hidden such as by the Tab Control?

I am using wave form Chart on a tab control. The problem is that the chart works fine when it is showing. I can stop the data and reset the chart history successfully. The Fun begins when I go to say Page 2 of Tab control ( The wave form Chart is on Page 1). If I now try to initilize my chart with offset, multiplier, min and max rage values - The chart assumes values on the X scale which are arbitrary. I can see this when I go back to Page 1.!!
But If Page 1 were showing and I did the same Operation The chart behaves as I expect it too.
Can this behaviour be explained? How do I resolve this Problem? Also I have Observed that from time to time the Sca
ling on X Axis may also change when the Chart is Hidden by the tab control. I have not been able to identify the reason for this, It is totally random.
Good Luck!
Mache
Attachments:
Time_Tab.vi ‏50 KB

I did a similar workaround ...
Everytime I Toggle the Run Button, I am making sure the active Tab is the one with Waveform Chart. This way the waveform Initializes fine. Then I try to Switch the active tab back to its One Previous Value, programatically - So that the user may have somewhat seamless interaction.
There is one hitch however - The waveform Chart needs some time to initialize and my data stream is also coming at every second. So if I switch Immediately to some other tab, Sometimes I am successful, Sometimes I am not. Again this depends om System Speed and such. If I update the Tab Control at the next iteration, it is very irritating visually. So I left the Tab control at the waveform chart after reset. If the User wants they can switch it Bac
k.
Of Course the best thing to do is don't Reset. Referred the problem to NI Apps. They said it will be fixed in the next version.
Well! Got to make enough money without resetting so that we can buy the new Version, which will reset!! Ciao! And Thanks for your answer.
Regards,
Mache
Good Luck!
Mache

How to keep the waveform chart updated when changing states in state machine/

Hello Everyone,
Can anyone please sugest me how to keep the waveform chart updated even if I am changing the states in a state machine??
I am having analog inputs on the waveform chart...
Thanks in advance...
Now on LabVIEW 10.0 on Win7

hello guys,
thanks a lot for the suggestions, here is the attached code... please follow the following steps to run it..
ONce you hit play,press either Start Main/Cyl UP button on the front panel,
once you start observing the waveforms, you can press the Cyl_Dwn button on the front panel... You can observe that the state changes to Start Counter state,
and the waveform chart also stops updating... I would like both the waveform charts to conitnuously show the data even if the state is changed....
Now on LabVIEW 10.0 on Win7
Attachments:
Soda Vending MAchine.vi ‏212 KB

Waveform CHart

Hai Friends
I have an one doubt in Waveform Chart.How Programatically add the plots in the chart and How to update the values for newly added plots.
Regards
Jai
Jayavel
Solved!
Go to Solution.

You can't change the number of plots without loosing the data history. You could read the chart history property then manipulate the 2D array, add the new data, then update the history data again. A simpler alternative if you know the maximum number of channels you are likely to need, is to set up a dummy 1D array of NaN's then when you get your data, use 'Replace Array Subset' vi to add your variable data to the chart. Take a look at my example.
Hope this helps.
Ian
Attachments:
Variable Plots.vi ‏19 KB

Configure x axes waveform chart

how should I configure the x-axes of waveform chart as I wanted it to be eff vs Iout.
Currently the setting I manage to generated is eff+Ioutvs time(bundle the signal of eff n Iout).
another would be Eff vs Ioutbut this only possible if the signal indexed into array.
But my requirement is to view the signal immediately rather than at the end when the process finished.
below is my attempt to generate eff vs Iout.(Which of course unable.)
Message Edited by 3den on 05-09-2007 08:41 PM

It's so much easier to just attach an image to your post by clicking on the browse button next to the attachment field below this message body.
It sounds like you should be using an XY Graph. The waveform chart will only plot a y value versus time. Use the Express XY Graph to plot as data is acquired or use the shipping example called XY Chart.

How to achieve this in waveform-chart?

I do use waveform chart in which 3 waveforms are stacked. My x-axis represent current time and y axis is a some quantity...Please look at the picture attached....is it possible to do this in waveform chart? Whenever mouse/cursor is on waveform it should display y-axis value corresponding to that point.......

Hi HS,
do you use 2 different logins?
If you would enable/show the cursor palette of the graph you would actually see those values instantly...
When you want to calc with them you can use the properties of the cursor to get the x- and y-value! No calculation of graph size and so on needed...
Best regards,
GerdW
CLAD, using 2009SP1 + LV2011SP1 + LV2014SP1 on WinXP+Win7+cRIO
Kudos are welcome

Waveform chart time sometimes decreases

I have a waveform chart with three plots vs time with update mode set to strip chart. It is demonstrating strange behavior which I have never noticed before. The time sample numbers at the extents of the axis sometimes decrease and the plots shift to the right instead of always left as I have always expected. Can anyone offer a plausible reason why this situation might occur?

the following applies only to charts that are Waveform data types, otherwise disregard.
Check the validity of the t0 values in the WF. If the timestamp is earler than the latest value plotted, the chart will reset.
Ben
Ben Rayner
I am currently active on.. MainStream Preppers
Rayner's Ridge is under construction

I use waveform chart VI to plot the setpoint as a g

Similar Messages

Maybe you are looking for