Custom scale for load cell

Hi
I am using a load cell to monitor an impact force. The load cell has a fixture attached to it which results in a non zero output. I am using a custom scale to convert the output from the load cell in volts to force to Newtons.
I am creating a custom scale and applying it to the task. I then want to be able to programmitically tare (zero) the load cell output before testing. However, my code does not work. There are no errors, but the gradient and intercept controls within the while loop do not function. Can anyone tell me why? I am aware that this could be done mathematically but I do not understand why the property node method does not work.
I am using labview 2010 with the latest version of daqmx (9.17 I think). My hardware is the USB-6211 card.
Many thanks.
John
Attachments:
custom_scale.png ‏53 KB

Hi John,
Thank you for a good description of the problem you are facing, as I understand it you have set up a custom scale but it doesn't seem to be functioning as you expected.
I have looked into this for you and have found a few examples which may help with the development of your application, I have also linked some articles for you.
The custom scale will need to be created entirely before the task is created, so any modifications can only be done before acquisition begins.
I hope this information is useful, and if you have any further queries please go ahead and post them and I will look into it for you.
Thanks
Stephanie L
Applications Engineer
National Instruments UK and Ireland

Similar Messages

  • Custom scale for counter input?

    Hello everyone,
    Is it possible to create a custom scale for a counter input? I saw there is a feature to allow input Custom Scale Name to the Channel Property Node. However, when I tried to create a custom scale to input to the channel, I got this error
    Error -200212 occurred at DAQmx Read (Counter DBL 1Chan 1Samp).vi:1
    Property: CI.MeasType
    Corresponding Value: Count Edges
    Property: CI.AngEncoder.Units
    Corresponding Value: From Custom Scale
    Channel Name: CountEdges
    Task Name: MyCountEdgesTask
    Do you know what is the problem with it? Thank you

    How do you have the channel set up? Can you attache the VI's that you are using? Is this a global virtual channel?
    Tim
    Johnson Controls
    Holland Michigan

  • Creating a custom scale for current

    Hi guys,
    I need some help with creating a custom scale. I am reading motor current (analog I/P) and would like to display that on a graph and write it to a file. I need to use a linear scaling for custom scale. The slope is 2 and the intercept is 0. I've attache the code to make it clear what I am trying to acomplish. The way I've set it up right now is no scaling. There are 2 tasks in the code. I would like to create a custom scaling for the first task as seen in the attached code. I have done custom scaling using DAQ Assistant Express VI. But I dont see such options when I try to do the same with the DAQmx task. Please let me know how this can be done. Any help is greatly appreciated.
    Thanks,
    Raj 
    Solved!
    Go to Solution.
    Attachments:
    Current_Voltage_RPM-_sub_VI-1.vi ‏18 KB

    You both had me going nuts trying to figure how to get to that property. Basically just right click the DAQmx property node and "Select filter..." . This brings up the "Configure Filter Settings" where I chose 'show all attributes'. I could then get to the AI Custom Scale Name property.
     Interestingly when you use the Property Browser and select the magnifying glass you can get to that property...but you just can't select it if you have the filter set incorrectly. Lesson Learned.
    I also found this community example and that one.  
    Using LabVIEW 2010SP1 and TestStand 4.5

  • Connection for load cell to NI9237

    Hi,
    I have this omega load cell part LCKD-10 which is a half bridge load cell that I need to connect to the NI9237. Please advice on the connection.
    Thanks
    Joelle

    Thanks. I need to write out a program which checks the centrality of force. I will be using 5nos of the omega load cell, 1 in the centre(Isolated) and the other 4 at all 4 corners. I'm suppose to firstly calibrate the load cell and then take measurement of the force applied to the 5 load cell and display the result in a form of a radar graph (Just a dot in the centre of the graph to show the centrality of the force). Appreciate if you can provide some procedures or program that I can use or try out.

  • Need for sugestion about DAQ Card for load cell

    Hi.
    I have a AT-MIO-16XE-50 DAQ card. But, I guess it doesn't work with load cell since it dosen't have output. So I need your regomendation about what DAQ card I should use. Also, if I need to use strain gage conditioner, recomende to me.
    Thanks
    Jee

    I couldn't find any information about a DAQ 512, but I did find info about a DAQCard-512 and DAQCard-500. If you meant one of these boards, then you will need NI-DAQ 6.9.3. That is the latest version of NI-DAQ to support these boards. Post again if you need additional assistance.

  • Creating a custom editor for each cell in a Jtable

    camirk, i know its swing ;) so
    http://forum.java.sun.com/thread.jspa?threadID=652383
    im just posting this link here for people who dont read the swing forum but are looking for the same solution
    hope it helps someone :)

    Two days after you posting you original question: http://forum.java.sun.com/thread.jspa?threadID=651625&messageID=3831712
    you find the answer on your own. Yes, the general Java forum sure is helpfull.
    If the question was posted in the Swing forum you would have had the answer in a couple of hours:
    http://forum.java.sun.com/thread.jspa?forumID=57&threadID=637581

  • Custom scale with Create Channel CI Position Angular Encoder

    Hi!
    In my application I use angular encoders for position measurement. I programatically create channel (task) using DAQmx Create Virtual Channel, CI Angular Encoder instance. Prior to that I use DAQmx Create Scale to create custom scale for the measurement, to convert from degrees directly to meters. The problem is that when I use the task (Start Task for instance) I get the following error message:
    Error -200378 occurred at DAQmx Start Task.vi:4
    Possible reason(s):
    Measurements: Custom scale specified does not exist.
    Custom Scale: RowCounter
    Task Name: _unnamedTask<66>
    Maybe somebody can help me out with this one.
    I use the same principle to create custom scales for AI measurements, and everything works without any problems. I know the scale is created properly, as I tried saving the custom scale to max after I create it. I then used the scale without a problem when I wired it as a constant to the custom scale input of the DAQmx Create Virtual Channel vi. It only gives me problems when I create it dynamically, using Create Scale vi.
    Some technical info: I use USB-6210 Daq card for signal acquisition.
    I will appreaciate any help!
    Jernej

    Hey!
    The error message I get is as follows:
    Error -200378 occurred at DAQmx Start Task.vi:4
    Possible reason(s):
    Measurements: Custom scale specified does not exist.
    Custom Scale: RowCounter
    Task Name: _unnamedTask<66>
    I use USB-6210 Daq card for signal acquisition. The error occurs right after the DAQmx Start Task.vi on the counter task.
    As I said, the code runs sometimes without problems and then sometimes it returns an error. I noticed that if I run the CustomScaleProblem.vi on its own it runs ok. When I open the project with mine application, from where I extracted CustomScaleProblem.vi part, and then try to run the CustomScaleProblem.vi, it stops working. It looks like when I open the project it allocates some space which is in conflict with the scale part of the code. Then if I close the Labview environment and open CustomScaleProblem.vi and run it, it runs again without any problem. Well, for now I did a work around the problem by saving the scale in the program and then using it. This approach works fine.
    About the arm start trigger. I use it because I dont want the counter to start counting before the AI task starts. I noticed that if I use the AI as a start trigger, and I move the encoder before AI starts, the counter will not start with 0, but will start with a number indicating the encoder movement before the AI start. Is that the right approach if I want the encoder to start
    counting from 0 when AI starts?
    Thanks and kind regards
    Jernej

  • Custom Scale behavior with DAQ Task running

    Hi to everyone, I am implementing a Polynomial Custom Scale for a sensor, but I have doubt about what happens if I change a Custom Scale and my DAQ Task is running, I suppose that the Custom scale does not change on the fly but my questions is if I have to clear the Task to apply the new custom scale or is enough with Stop the Task and Start the Task again.
    I am using the DAQmx functions for the code. Thanks for your help.

    Hi AYanez!! 
    Thank you very much for using NI Discussion Forums!!  I found a post that deals with the same issue you are trying to solve for your application.  It seems that you have to stop the task for the new scaling properties to be applied.  Take a look into this thread:
    Programmatically applying a custom scale in an active VI
    Hope this helps!
    Regards,
    Anuar R.
    National Instruments México y Latinoamérica
    Ingeniería de Aplicaciones
    www.ni.com/soporte

  • "connecting a load cell to scb-100"

    I have an scb-100 and want to know if it is possible to connect a load cell to it and if so, how.

    It is probably possible, but you have to have some additional circuitry in order to use the load cell. Typically, load cells are comprised of strain gauges which require some kind of Wheatstone bridge completion. Additionally, most strain gauges need excitation. If you can provide the bridge completion and excitation, then you could simply read the output of the strain gauge by connecting the output + and - to your SCB-100. However, setting up this external circuitry can be a little complicated. So, the recommended setup is to use some signal conditioning. National Instruments provides a couple of options regarding signal conditioning for load cells. Below is a link to a tutorial that discusses how to measure a load cell and what hardware is recommended for
    that. I hope this information helps.
    Tutorial

  • API for loading Bank account details for the Customer

    Hi,
    Can anyone tell me what is the API that needs to be used for loading bank account information for the Customer?
    Thanks
    GM

    Hi,
    Were you not able to achieve your requirement with Customer Interface Program?
    There is a interface table 'RA_CUSTOMER_BANKS_INT_ALL' which is used to store customer bank account information. Run the program after inserting the records into this table.
    I guess, there is no public API.
    Regards,
    Ram

  • Question on Measuring Lift Force for MAV Ornithopter for Student Project using Load Cell

    Hey everyone!
    I am new to these forums so bare with me, please. I am part of a senior design student group working on making a micro aerial vehicle ornithopter (generates lift by flapping its wings) similar to this Design.
    We are using this load cell connected to an AD620 Op-Amp circuit that basically has two input wires from the load cell coming into the op-amp with a gain of 100 (there is an Rg resistor with 500 ohms in the circuit). The load cell and op-amp circuit are both powered correctly with 10 V and +-15 V, respectively. There are two output wires coming out of the circuit. One comes out of the 6th terminal of the op-amp, and one is connected to ground. If we turn on everything and test the output of the circuit with a multimeter there is little if no fluctuation in the output voltage, which is about .25 V with zero load. If we add precise weights and form a linear graph of the output voltage vs. weight, we can find that there is about .0045 volts/gram relationship.
    Here comes the part we we are having trouble. It seems as though the circuit it working correctly, but when we try and hook it up to our USB-6221 DAQ Board though the ai0 (or any analog input) and confirm a LabVIEW program to read the output, we get a ton of noise along with a weird looking graph.
    Here is a picture of the front panel that shows the output we are getting http://img130.imageshack.us/i/frontpanelg.jpg/
    Basically, I would have though we could get a straight line that continuely increases or decreases depending on the load on the load cell. Why would it graph a ton of vertical lines? I would think it would be just one data point per time value?
    Here is the simpler block diagram just to test the output: http://img26.imageshack.us/i/blockdiagramsmall.jpg/
    Here is the main block diagram that we were going to use to convert to force, etc. but its not working (no need for while loop?): http://img15.imageshack.us/i/blockdiagrambig.jpg/
    The properties of the DAQ Assistant VI is as follows:
    input range: -10 to 10 v
    RSE terminal configuration
    acquisition mode: n samples and not sure how many samples we want to read or how fast. we had 1k hz and 100 samples and the image above is basically what we got it the program runs continuously. 
    I don't know what else I can tell you, except that if anyone helps me you would be like a godsend to our group. It would be very much appreciated
    Thanks!!!

    As I am unable to look at youor images (the corporate filter here is blocking the url) I can't see what you are describing. I will say that a multimeter will not show fast transitions that will show up in a LabVIEW/DAQ application, so using a meter usually doesn't tell you that much about signal "cleanness". How long are the wires from the op amp/load cell to the DAQ? How long are the wires, and what type (shielded, twisted pairs, untwisted pairs, etc.) from the load cell to the op amp. The output levels of the load cell are usually quite low, so the possibility of also picking up "environmental" electrical noise is very high, and this will be amplified as well. Since the output of the op amp is higher, the noise introduced between it and the input to the DAQ is less of an issue, but there as well. So making sure that signal wires are properly shielded and grounded is important, and there are long papers describing this for low level analog signals. Since the load cells desired output will probably vary relatively slowly (a few Hz) it may also be helpful to put a simple low pass filter before the DAQ.
    You should insert the images into your post, as jpg, or png (you have jpg images) Not bmp! (this is for others that might read your post, yours are jpg which should be ok). Generally most of us won't or can't go to links, corporate network filters and corporate policies frown on it, too much maleware lurking at the end of unknown URL's
    Putnam
    Certified LabVIEW Developer
    Senior Test Engineer
    Currently using LV 6.1-LabVIEW 2012, RT8.5
    LabVIEW Champion

  • Is it possible to condition a load cell signal with a 1520 SCXI and then use it as the primary analog feedback for a 735X motion control board?

    My system
    PXI 1052 chassis
    PXI 8196 RT controller
    Flexmotion 7356 motion controller
    Flexmotion 7354 motion controller
    6259 M series DAQ
    1520 SCXI
    1520 SCXI
    1314 SCXI frount mounting terminal block
    DSM strain gage load cells
    Exlar SR Brushless PM motors
    Kollmorgen servo star CD series 5 drives
    My objective:
    I want to measure the force on the load cells with the 1520 SCXI (i.e. excite the load cell then amplify and condition its output) then I want to use this analog (force) signal as the primary feedback for my motion control system (7356 and 7354 motion controller connected to my drives and motors).
    The problem:
    The motion controller boards (7356 and 7354) can be configured for force feedback control via analog feedback from a load cell.  However the boards implicitly expect the load cell signal to be amplified and conditioned with and external signal conditioner rather then using an NI SCXI module.  Currently I’m am reading the SCXI signals via the 6259 M seriers DAQ and consequentially have no way to route the signal into the 735X boards for force feedback control.  I can use softmotion to control the motors but then I loose the fast PID update rates possible with the 735X boards.
    The question:
    Is it possible to condition a load cell signal with a 1520 SCXI and then use it as the primary analog feedback for a 735X motion control board? 
    Thanks
    Patrick Aubin
    Ph.D Candidate
    University of Washington &
    VA MedicalCenter of Excellence for
    Limb Loss Prevention and Prosthetic Engineering  

    Hi GG,
    Thank you for your feedback.
    >create your own external circuitry to amplify the signal.>
    True a few op-amps could amplify and filter the signal externally but the performance of such an amateur built system will never match the accuracy and functionality of the 1520 SCXI.  That’s why we spent the $2500 for the professional version.
    >One thing that you could do is to use a UMI with your motion controller and then wire your signal from your SCXI to the UMI.>
    As I understand it the UMI is basically a break out connectivity interface for third party drives.  After conditioning and amplifying the analog force signal with the SCXI module the analog signal isn’t available to wire into a UMI.  To my knowledge the conditioned signal of the SCXI resides only in the PXI backplane (i.e. there is no physical access to the conditioned analog signal).  Can you explain how the UMI could be help here.
    Again thanks for your input GG.
    Patrick

  • Interface for loading data into customer products

    I am trying to find if there is any interface for loading Customer products in Install Base apart from entering them manually. I understand that this exists in Oracle Apps version 11.5.7 but I need this for version 11.5.4.

    Hi,
    In 11.5.4 , you've to write yourself the loader, using Oracle standard API.
    I've performed it, it is working fine.
    Hugues

  • Does National Instruments produce a DAQ equivalent of an electronic load for fuel cell testing?

    I am trying to consider my options before purchasing an electronic load. I would like to use LabView software to record and analyze my data that I will be generating during fuel cell testing. I was just wondering if National Instruments produced an instrument similar to an electronic load or a couple instruments that could work in combination similarly to an electronic load. I have looked through the available DAQ instruments on the NI website and it seems that they all output signals too low for my application. The fuel cell I will be using outputs voltage from 0-2VDC and current from 0-4A. I understand the internal workings of an electronic load and realize that the best option would be to implement some sort of variable resistor to act as the load in my circuit, then use DAQ instruments to measure current and voltage respectively. The problem is that the range of my current, especially, is much larger than any allowable input range for any NI DAQ instruments.
    Any input would be much appreciated. Also if you have developed a testing system for fuel cells or other low power DC sources, please share any knowledge and information about how you went about designing your system.
    Thanks

    TravisW wrote:
    I am trying to consider my options before purchasing an electronic load....
    Any input would be much appreciated. Also if you have developed a testing system for fuel cells or other low power DC sources, please share any knowledge and information about how you went about designing your system.
    Thanks
    We used a DC Programmable Electronic Load from AMREL.
    WE used GPIB to talk to each of them The loads ley us set constant current/voltage and let us query the current values etc.
    Worked fine for us,
    Ben
    Ben Rayner
    I am currently active on.. MainStream Preppers
    Rayner's Ridge is under construction

  • Elements 13 will not custom scale a photo for print.

    When I try to custom scale a photo, the sizes have no effect on the finished photo and leaves a vertical bar on either side in Elements 13.  Elements 12 worked much better.

    Alec
    AdobeTV
    Products | Premiere Elements | Adobe TV
    Premiere Elements 13 Guided Section
    Do not overlook the program itself. It has Expert Guided and Quick Guided for special topics such as
    Getting Started with Premiere Elements
    Trimming Unwanted Frames
    Adding transitions between Video Clips
    Adding Scores to your movie
    Adding Brightness + Contrast & Color
    Adding title to your Movie
    Adding Narration to your Movie
    Creating a Picture in Picture
    Animate graphics easily
    Adding Video In Title
    Apply an Effect Mask to your Video
    Premiere Elements 13 Help PDF
    https://helpx.adobe.com/pdf/premiere-elements_reference.pdf
    Elements Organizer 13 Help PDF
    https://helpx.adobe.com/pdf/elements-organizer_reference.pdf
    And, please never hesitate to ask questions and ask for clarification here in the Adobe Premiere Elements Forum.
    Lots free support to explore.
    I would start going through the Guided lessons in the Premiere Elements 13 Editor.
    Please update us on your progress as your schedule permits.
    Best wishes
    ATR

Maybe you are looking for