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Not able to remove spaces from ASCII code Hex string

Hello, Good Evening

I have am facing problem with this VI i am trying to remove space from the concatenated string i have used many ways to remove space but i am not able to remove space someone please help me with this errorImage may be NSFW.
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Capture5.PNG


cannot see the block diagram when i open the vi

Hi,

Till yesterday, I have made changes to the block diagram of the VI i was working on.

Suddenly, the block diagram is not accessible. What could cause this? The front end seems working perfectly fine. I just cant access the back end. 

I have some important stuff in that file. 

Exception: Access violation (0xC0000005) at EIP=0x00F93B10

When start LabVIEW 2014, it crashed with following exception: 

Exception: Access violation (0xC0000005) at EIP=0x00F93B10

Any suggestions?

Read values on text file

Hello I would like to read the values from the treatment of a first VI in a second. The data was saved from the text file I can not do it, I try the process in vi I send it to you.
Here is the capture of the text file and the data I want to read.
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CaptureM.PNG

 

Waveform generation and phase angle

We are trying to use NI USB-6216 DAQmx board to generate and receive waveform signals to mimic the function of a phase angel voltmeter, I attached snippet for signal generation part of the code.

 

If the signal is measured by North Atlantic 2251 phase angle voltmeter, the measured results are stable and accurate, usually within a fraction of degrees. If we measure the signal by the DAQmx board input channels (generate and receive on the same board), the measured results are not very accurate, in range of one or two degrees for 1k Hz frequency, more error with higher frequency. Also the results are not repeatable, every time we start the signal generation, we read a new value. 

 

We consider the possible cause is that the quality of generated signal is not good enough, we hope someone with this kind of knowledge can give some suggestions. Let us know if you need further details.

order a vector from highest to lowest using recursion

good morning, I'm performing three Vi consisting of a main, and two sub VI, in the first sub VI the values are entered using a structure event in which every time the button is priced it stores the value in a vector, the next Sub VI takes that vector and sorts it from less than large, but this sub VI must have recursion to sort the vector, the vector entered in clutter and ordered is shown in the main VI. my drawback is that I don't know how to develop recursion maybe you can help me please. attached my files

Saving TIFF files with compression, tag settings

I need to alter single-page TIFF files that are generated by an upstream non-LV process and get consumed by a downstream non-LV process.  I do not have access to or details of either the producer or consumer processes and so I am trying to save my modified version of the TIFF using the same conditions as the original.    Does anyone have insight on how I can save the files as LZW-compressed?   This is a short duration development-mode experiment where I might have to alter ~500 files <10 times so a slightly time consuming, inelegant (but automated) route is OK.

{Win7-64, LV 2015 Pro Dev SP1, Vision Dev Module 2015}

I ran AsTiffTagViewer on the files:

  • Original file (4.52 MB):
    • ImageWidth (1 Short): 15778
    • ImageLength (1 Short): 11275
    • BitsPerSample (1 Short): 8
    • Compression (1 Short): LZW
    • Photometric (1 Short): MinIsWhite
    • FillOrder (1 Short): Lsb2Msb
    • StripOffsets (11 Long): 310, 505045, 970733, 1490967, 1969833,...
    • Orientation (1 Short): TopLeft
    • SamplesPerPixel (1 Short): 1
    • RowsPerStrip (1 Short): 1025
    • StripByteCounts (11 Long): 504735, 465688, 520234, 478866, 387217,...
    • XResolution (1 Rational): 751
    • YResolution (1 Rational): 751
    • PlanarConfig (1 Short): Contig
    • ResolutionUnit (1 Short): Inch
    • SampleFormat (1 Short): 1
  • As modified and output from "IMAQ Write File 2" (169 MB)
    • ImageWidth (1 Short): 15778
    • ImageLength (1 Short): 11275
    • BitsPerSample (1 Short): 8
    • Compression (1 Short): Uncompressed
    • Photometric (1 Short): MinIsBlack
    • FillOrder (1 Short): Msb2Lsb
    • StripOffsets (1 Long): 8
    • Orientation (1 Short): TopLeft
    • SamplesPerPixel (1 Short): 1
    • RowsPerStrip (1 Short): 11275
    • StripByteCounts (1 Long): 177896950
    • XResolution (1 Rational): 751
    • YResolution (1 Rational): 751
    • PlanarConfig (1 Short): Contig
    • ResolutionUnit (1 Short): Inch
    • Software (28 ASCII): National Instruments IMAQ
  • IMAQ output re-saved with LZW in GIMP (6.18MB)
    • SubFileType (1 Long): Zero
    • ImageWidth (1 Short): 15778
    • ImageLength (1 Short): 11275
    • BitsPerSample (1 Short): 8
    • Compression (1 Short): LZW
    • Photometric (1 Short): MinIsBlack
    • StripOffsets (177 Long): 8, 33865, 79942, 123014, 169668, 212038,...
    • Orientation (1 Short): TopLeft
    • SamplesPerPixel (1 Short): 1
    • RowsPerStrip (1 Short): 64
    • StripByteCounts (177 Long): 33857, 46077, 43072, 46654, 42370, 46516,...
    • XResolution (1 Rational): 751
    • YResolution (1 Rational): 751
    • PlanarConfig (1 Short): Contig
    • ResolutionUnit (1 Short): Inch

LabVIEW Unstable Digital PWM Output to DAQ

I am using the attached VI in attempt to output a variable/controllable digital PWM wave from a NI USB-6356,6366 DAQ. However, my oscilloscope reading is quite unstable compared to using the DAQ Assistant's test output. As seen below to the left, the code generated square wave's duty cycle seems to be oscillating rapidly. It is set to 100 Hz and 50% duty cycle on the front panel. To the right is the stable signal from the DAQ Assistant.

 

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Code Generated.jpg
Labview Code Generated
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DAQAssistant Generated.jpg
DAQ Assistant Generated

The bulk of the code was taken from: https://forums.ni.com/t5/Example-Programs/Software-Timed-Pulse-Width-Modulation/ta-p/3507768

 

Please advise. Thank you.

 

 


Using LabVIEW to send a command using NI-VISA and reading constant Temperature using the labview Thermometer

I have attached the datasheet of a Delta Oven.

I want to be able to read the temperature at all times using LabView and I guess NI-Visa is not possible with DAQ.

 

Also what command from the datasheet is used for DWELL Time(like staying at the set temperature for x amount of time)??

 

Commands are on page 51 Table 5-3

 

cRio motor safety sensor

I am new to LabVIEW. 

 

I am using a cRio with analog in, analog out and digital out to control the extension and retraction of a motor to test and validate forces, stroke of a hydraulic cylinder. 

 

I want to send the motor all the way back to an almost fully retracted state if the load cell measures that the motor is exerting over 220 lb. I am using a case structure to handle the different cases (ie Fully Extended button is pressed, motor exceeds 220 lb , etc)

The program works well other than not having a good way to send the motor back to a retracted state. The current VI will retract only until it drops below 220 lb, then goes back into extension, then again triggers the retract case since its above 220 again, back and forth. 

Basically I need the motor to retract no matter what if the motor exceeds 220 lbs until the motor distance sensor reaches a certain value. 

 

I hope I explained this well enough. 

 

I know the code is messy. 

 

 

Note i am using a test cylinder with a 10lb max compression here. 

 

 

 

Nick 

Immediate need Sr. Software Engineer

I have an immediate need for a Sr. Software Engineer. Location is Cheshire, CT. 06410. This is a permanent position with full benefits. Super company! LabVIEW  v.2005 to present is fine. If interested please email resume to: pkenny@encorenj.com

 

Job Description 

Automation Software Engineer Industrial Controls 

 

  JOB SUMMARY:

Design and maintain control software used in chemical automation equipment. This will include programming, testing, and remote customer assistance in the deployment of solutions used in the field.

 

ESSENTIAL DUTIES AND ACCOUNTABILITIES:

  • Provide the technical expertise required for computer & PLC setup, programming, and troubleshooting.
  • Planning/writing of programming code as necessary, to ensure the end product meets functional goals expected of the product on required schedules.
  • Provide on-site assistance during system start-up, commissioning and maintenance
  • Support the creation of technical product documentation and information
  • Estimate and report on project status
  • Assist field technicians in troubleshooting applications.

 Qualifications:

  EDUCATION and/or EXPERIENCE:

  • BA/BS degree in computer science, computer engineering, or related field;  equivalent experience will be considered
  • 3+ years programming experience preferred

TRAVEL REQUIREMENTS:

  • Occasionally (Up to 20% of work time)

 

COMPUTER SKILLS:

  • Experience with Google Docs
  • Git experience is a plus
  • Experience with C# is a plus
  • Experience with LabVIEW
  • Robotics experience is a plus

 

COMMUNICATION and/or CRITICAL THINKING SKILLS:

  • A strong desire to learn and apply new skills
  • Ability to read, analyze and interpret general business periodicals, professional journals, technical procedures, or governmental regulations  
  • Ability to write routine business reports and business correspondence in English  
  • Ability to effectively present information and respond to questions from employees and/or customers
  • Ability to solve practical problems and deal with a variety of concrete variables in situations where only limited standardization exists
  • Ability to read and interpret documents such as safety rules, operating and maintenance instructions, and procedure manuals using the English language

 

STEM SKILLS:

  • Advanced mathematical skills relevant to the engineering application
  • Basic thermodynamics knowledge a plus

 

 

 

Help with Texas Instruments VI

Hi, I am looking to communicate to Texas Instruments LMP91300 and am looking to use the TI created LabVIEW VI for their SWIF communication protocol given in the below link.  I am currently in the process of purchasing LabVIEW Professional 2019 and want to ensure compatibility with that VI.  Currently, I am using TI designed GUI to communicate to the chip through an evaluation board, but this is very tedious and manual process and I want to automate it in LabVIEW.  

 

I initially sent this in to NI as a support ticket, however NI technical support said they cannot make the VI work due to some errors and they closed the ticket.

 

I contacted TI and they said they do not support the device anymore so they cannot give me any help on making their VI work.

 

I  know this VI works because I know of an organization that is currently using it.

 

Can someone here help me?   

 

https://e2e.ti.com/support/sensors/f/1023/t/511837

 

Splitting Strings by Character Number

I'm trying to find a way to differentiate duplicates of files based off of their revision. Two files are the same but of different revision if they have the same file name, but a different suffix (always a capital letter) at the end.

 

For instance:

ABC123A.xxx

ABC123B.xxx

are both of the same file but of a different revision. 

ABC122A.xxx

ABC123B.xxx

are of different files and different revisions.

 

My problem is that I need to be able to determine if two files are the same but of different revisions. My idea for a solution was to strip the file extension, then split the remaining string into two, one being n-1 characters long, and the other being 1 character long. Is there a way to do this? All split string methods I've seen so far either require a complete match or a delimiter.

 

Thanks!

assumed erronous amplitude in low end of frequency spectrum

I use PSD function to get the amplitude spectrum of accelerometers on a pump, thru a DAQ device.

im sampling at 25600hz, using 512 samples once every second for the spectrum.

 

i dont do any averaging, as i had some difficulties making it work as i expected.

 

even when the pump is at standstill im picking up high amplitudes in the lowest or second lowest frequency bin. 

 

see attached pic: frequency spectrum mms2

 

when i do frequency domain integration, these amplitudes become more prominent. note that i set the 0hz bin to zero after the integration, as i didnt figure out how to do integration at 0hz.

 

see attached pic: frequency spectrum mms

see attached pic: frequency spectrum mms zoomed

 

If i turn off windowing; hanning -> rectangular, then these amplitudes almost disappear. maybe because spectral leakage smooths it out? blackman window made them larger than hanning.

 

Is there some known reason this could happen, is there some simple way to correct? my plan forward is to increase frequency resolution (use 8000 samples maybe) enough that i can drop the lowest bins from measurements, hopefully the pc will handle it.

 

i dont have VI available to post as im writing topic.

pulse triggered output

I drew two structures to make an input peak triggered output, one is producer/ consumer, and the other is just a case structure. but when I test the result, the trigger value didn't show a pattern. the trigger pulse follows the peak boolean true value, but it did not trigger after an input peak, I changed different threshold and width and did not see any trigger follow a peak. did I use the peak detector wrongly? or the structure causes a huge delay?


How do I plot data that is larger than 1 among the data I collect with DAQ separately?

How do I plot data that is larger than 1 among the data I collect with DAQ separately?

 

So I try to insert the '>' function into the 'case' function when the data value is greater than 1, but it is impossible.

 

Can you fix this? Help.

Reg buffered shared variables explanation

Hi,

 

I am in process of understanding the functioning of network published Shared variables. I was trying to use buffering of SVs in order to utilize it for application.

In a project I created 2 libraries, one hosting a double type server SV with 50 buffer capacity. In another library I created an alias variable as client.

These variables were accessed in different VIs. The server VI was writing random data to the server SV. In another VI I am reading the data from client SV.

When I stopped my server vi the client vi also stops updating and keeps the last data value. 

My query is regarding the use of buffering in SVs. I was expecting that the client SV should still has 50 elements after the server vi is stopped. Or there should be some delay in update of data in client vi but I did not observed anything. As soon as  the server vi was stopped the client vi stopped in updating data.

 

Can anyone explain the use of buffering in SV. 

Thanks

data is transfering via VISA write, but different values are coming

i am giving 5 bytes of data, data is transfering into VISA write operation but at output side different values are getting,

    how can i reslove my problem,

i given a screen shot of my VI please gothrough it,

   please sugguest  me.

 

Re-install Labview 2016 after Uninstalled using NI package manager

Hi, I was trying to reinstall Lab view 2016 which I had uninstalled using the NI Package Manager and during the installation it give me a message saying "NI Lab View 2016 (incompatible with products already installed)". I'm suspecting this might due to an incomplete uninstall from the package manager. Please advise me on how to reinstall the Lab view again. Thank you!

Error 8 occurred at Read File+ (string): Read File


Hello, I am trying to access aspen dynamic simulation data through excel into labview.

The issues I am facing is that the excel file I have to save in csv which I get but due to that the excel file has to be manually saved. when I save the file labview brings up the following error:
"Error 8 occurred at Read File+ (string): Read File"
"LabVIEW: (Hex 0x8) File permission error. You do not have the correct permissions for the file."

If there is anyway I would like to automate excel so that the labview file auto saves and reads the excel file forgoing the csv error and save dialog. I would like this to happen real time.
Please help I am really stuck.
I have attached both error screenshots.
I have attached the screenshots of both the excel dialog and labview error.

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