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Re: Raltime XY Chart

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I suspect the problem you're having relates to your "2 stream data set"? If you have arrays, this is simple - bundle the arrays and connect to an XY Graph.

Perhaps you mean you're getting a subset of points each iteration of a loop, and you want to append these to a graph?

 

In that case, you can use one of 3(?) formats - an array of points (cluster of X and Y), a cluster of arrays (X array, Y array) or an array of Complex numbers (Re, Im).

The 3rd option is quite straightforward if you use the Build Array and Re/Im to Complex nodes.

 

A comparison of the methods can be seen here:

Example_VI_BD.pngComparison of bundling options

 

This was taken from another thread I answered, but hopefully it's clear that I have two individual DBL numbers (one for X, taken from the difference in time, and the other for Y from the string conversion over serial port) and I'm creating 3 different arrays on the Shift Registers (you only need to pick one of these options) and connecting it to an XY Graph (named Buffer).

You can get a link to the other thread if you're interested to read more by clicking on the image, and under the kudos/download buttons, there should be "publishing history" or similar. This thread and one other will be linked.


Re: VI Farenheit and Celsius set up HELP

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 wrote:

Which solution is easier to program? Which solution provides a quicker way to change formula?


Hmm... guess it depends if I can guess right with the formula node or need to open the detailed help to get the right syntax...

I'd be tempted to disagree with what I expect is the desired answer based on the nice quick-drop plugins...

Re: LabVIEW-Ladefehlercode 17

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Try a Mass Compile. If that keeps failing, try finding the culprit. 

 

Especially when upgrading from an older LabVIEW version (younger than LV2019) you need to check that the code is still fine. Open your methods and see if you can fix things. It might be that there is a broken method or one that just needed a recompile.

Re: data acquisition

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There is of course the official documentation: https://en.wikipedia.org/wiki/Nyquist%E2%80%93Shannon_sampling_theorem

 

However, my rule of thumb is to go 10x faster than the expected signal rate when acquiring data. With this you could still distinguish 9.0 and 9.1 GHz. 

 

But 9 GHz ... that's really fast signal. I don't think there are any signal acquisition boards from NI available for that. For that speed I guess you need a device between the acquisition and the sensor. I tempted to advice you on radar acquisition devices. Those aren't cheap, but do the trick. Call someone at Keysight. I guess they can do also FFT and spectrum analysis tools, saving you time on the data analysis.

Re: How do I give remote access for a Universal Robot UR3e using LabVIEW

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Hello,

 

Yes, with the VI example, you can control a UR3e. The machine that runs LabVIEW and the robot should be on the same local network.

The given VI is a small example. It allows you to remote power on the robot, release brake and remote send a line of UR Script. But, you can customize this example for your own needs.

All features are located in the DLL \Libraries\net40\UnderAutomarion.UniversalRobots.dll, and documented here : https://underautomation.com/documentation/

The library allows you to load a program, play a program, pause a program, check if a program is running, stop a program, check safety, read io, read robot position, etc...

 

For your case, it seems that you want the VI to play a program. It's simple, in the VI provided, you just have to replace the call to the "PowerOn()" function by a call to the "Play()" function. Idem for pausing a program.

The LabView block "Invoke node (.NET)" allows you to call a function that remote control your robot.

As you can see, a lot of commands are available :

 

callNET.pngAdd a call to a function

 

play.pngChange a function call

 

Issue with CPU Cores not being utilized when run on High Configuration Server

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Hi,


I have been working on a LabVIEW application to simulate certain parameters and write them to MongoDB on the localhost. The data to be written is huge in number and I have been using For Loops Iteration parallelism for multithreading. When the application is run on the desktop with windows 10 (i5, 4 Logical Processors, 2.6GHz) it utilizes maximum CPU(~95%) and is completely stable.

But when the same application is being run on the Server PC with Windows server 2016(Xeon Silver,40 Logical Processors, 2.6GHz) only 1 Core is being utilized and the total CPU usage is around 5%.

Any suggestions on how to utilize the CPU cores to the fullest?

Jatin Verma
Applications Engineer
AvGarde Systems

NI 1722

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Hello Sir/Madam,

This is Faraz Ahmed here, King Saud University. I have NI 1722 smart camera, Serial number: 325 13 060, part number: Rl 1424-660 NI.

I want to know if this monochrome camera be able to automate crack monitoring in Fatigue testing machine. As this can facilitate us for automated calibration of values rather than observing the crack with our naked eye.

 

Please answer this. Thanking you in anticipation.

 

Regards,

Faraz Ahmed,

+966-593864751.

Re: NI 1722

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Hi Faraz,

 

why don't you call your local NI support team to discuss capabilities of NI hardware and the needed software?


Re: Read From Binary file : memory leakage?

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Hello,

I understand that I can spit my data of course. But this does not explain the issues that I referred to in my original message. Also I still do not understand how to free the memory used between the readings...

The intermediate memory usages that I display on the front panel still puzzle me...

Thanks

Christophe

Re: Re : Insert image file to word document using active X

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Many thanks, I modified the code accoding to your recommendation.

 

Thanks

Gabor

Re: Stereo sound generation

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You can use two copies of Basic Function Generator.vi, then build an array of waveforms to create a stereo pair (where index 0 is the left channel). The array of waveforms can then be written to the sound device configured in continuous sample mode.

 

Two Tones.png

Thermocouple Temperature Shift

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Hello there,

I am having an issue with my thermocouples type k. I have configured them using a "DAQ Assistant" by selecting the appropriate analog input, defining them as thermocouple type k, setting the cjc to "in built" and the "auto zero mode" to "every sample".

At the beginning the measured temperatures look quite promissing (about 21.8° in a lab where other Temperature Sensors show about 22°), but with time, or better said in the evening, these values shift to much higher values (about 24.x°). What can cause such an issue?

One guess is that the electronics (and the surrounding electronics), respectively the heat which they are emitting, is disturbing the cjc/reference measurement? Can such a behavior appear becaus of the age of the NI-Modules?

At the moment three modules (see list below) are mounted on the "mainboard", directly one next to the other. The board itself is mounted in an Electrical Control Panel.

As an absolute electronics and LabView beginner I do not really know what to try next and therefore would be happy for any suggestions!

The used Block Diagramm is attached. If you need further information or if anything was not explained good enough please let me know!

Regards,

TCNoob

Used Hardware:
-NI cDAQ-9188

Mounted on the above board:

-NI9211 (3 Thermocouples Type k: T-PreCooler, T-AfterCooler, T-ProdVessel)

-NI9207 (used for other signals, such as T-R and T-Set and Pressures in the attached Screenshot)

-NI9481 (used for a heater... not important for this problem)

 

 

 

Re: Stereo sound generation

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Off topic...


 wrote:

Edit: Why the heck is there so much whitespace on this post?


 

<div id="styleDivScrolling" style="height: 766px;"><p>Edit: Why the heck is there so much whitespace on this post?</p></div>

 

style="height: 766px;" caused the problem.

 

Not sure how that ended up there. Selecting everything and then clicking "clear formatting" (the Tx icon) should remove all formatting. Or go into the HTML view...

 

With modified HTML:

 

<div id="styleDivScrolling"><p>Edit: Why the heck is there so much whitespace on this post?</p></div>

 

 


 wrote:

Edit: Why the heck is there so much whitespace on this post?


 

Re: Read From Binary file : memory leakage?

Re: Cannot connect to SQL databank from a different account

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Thank You very much for the clarification. My programming skills are limited to LabVIEW and MATLAB. My interest and experience is in LabVIEW, so I got a job in that. I guess LabVIEW is not just enough. Thank you again.


Re: Problem controlling stepper motors

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The technique you're missing is probably shift registers.

 

Put the positions (also known as "setpoints") in an array.

Give your loop a shift register.

Wire the array with setpoint to the left side of the shift register.

Get the first element, and use it to set the motor position.

When the setpoint is reached, delete the element.

Wire the resulting array (with or without the deleted element) to the inside right side of the shift register.

 

An image will probably be more useful:

Positions.PNG

Keep in mind that I don't know your program as well as you do.

 

Lots of variations are possible. Some are probably better. You can for instance keep the position index in a shift register, in stead of the array itself. Or you can rotate the positions in stead of deleting the elements, if you want an infinite loop.

 

You've done a good job so far. But do try to use CTRL + ALT+ mouse drag to remove some of that empty space. A big diagram means less overview, and more work to get things done. You can always insert the space with CTRL + mouse drag if you really need it.

Insert two numbers in one array

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Hi,

I have done a program in which I have to insert to different numbers in one array, and I don´t know why, but it inserts one number and when it has to insert the other one it eliminates the previous number. I attach one picture to see more clear.

insert number.PNG

The blue line is connected to the array where I want to insert the two numbers.

Best regards

Re: Issue with CPU Cores not being utilized when run on High Configuration Server

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Just a simple question (probably you already handled this), but how are you specifying the parellelism (and less importantly, chunking) with the loop?

As you know, configuring parellelism creates a "P" node under the "N" - this can be wired with a value to specify the number of paralllel processes desired.

If you don't wire this, I believe it will use what you choose when you configure the loop, which will perhaps be the 4 from your Win10 PC (assuming you developed the code there and copied it to the server, perhaps via SCC etc).

You could consider determining this value at runtime if you might use your code on various different computers and you know the time in the loop will be large compared to the time to work out a value for P.

 

CPU Information node will give you the values you need, although on my workstation I couldn't get above 50% (I suspect hyperthreading effects).

Re: Issue with CPU Cores not being utilized when run on High Configuration Server

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I had a discussion with NI a few months ago. Windows Server 2016 is not a supported OS, and it probably will never be...

Have you tried to use two independent parallel loops , e.g. a repeated FFT calculation in one loop and in the other your MongoDB application, if LabVIEW will utilize more than one core?

Re: Insert two numbers in one array

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You branch the wire (blue, thick array wire) and so you have two different arrays.

You need to pass the array through continuously.

You probably also want to read about Shift Registers.

 

I will also suggest the learning materials at the top of the forum 😉

 

Here's a quick example for Replace Array Subset (which may or may not be what you want - consider also Build Array or Insert Into Array).

Example_VI.png

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