Measuring 100K signal from piezo electric sensor

Hi programmers,
                             we are using a compact rio with 9215 module to measure a signal of 1KHz and it works fine. When we want to measure a signal of 100KHz from a output of a  Piezo sensor, it doesn't. when we inputted a signal of even 10KHz from a standard signal generator, there was no response. So now we want to upgrade our program to measure the 100KHz signal, can anybody suggest solution.
Thank you
Labview lovers.

Hi!
   I'm worried about the fact that 10 kHz signal isn't seen, that cRIO module is rated for 100 kS/s per channel, so, with 1 channel, you should theoretically be able to sample as high as 50 kHz, or, with common approximation, say 20 kHz.
   To better understand your problem, let me ask you: what do you mean when you say "no response"? How many channel are you using?
Have a nice day!
graziano

Similar Messages

  • Acquring signal from piezo sensor

    im new to labview.im using usb-6251 to read voltage from a piezo sensor. i started off by reading the voltage with an avometer and it read 0 volts at free strain now i used a BNC cable to wire the piezo to the analog input channel and read it using the daq assistant there was on offset of about 1.7 volts when i used floating source configuration. when i used ground ref source configuration the readings were not reasonable it kept drifting while im not applying strain and whever i touch the insulator of the cable the reading keeps going from min voltage to max voltage. i made sure of the positive and negative terminals and that im reading from the correct channel.any help with the configuration or a possible reason for the problem would be appreciated . this is a screenshot of the readings while using floating source and no strain applied (it should be reading zero)

    An "AVOmeter"?!?  Haven't heard that term in... well actually ever.  But my dad used to have a "Megger" so I know what you mean.
    It sounds like your electrical setup is probably wrong, not your DAQ.  What kind of piezo are you using?  What kind of signal conditioning circuit is conected to it and what signal does the circuit output???
    EDIT:  Added avometer wiki-link.

  • Measuring Digital Output from 3 Hall Effect Sensors

    I'm working on a project where I need to map the digital signal coming from 3 hall effect sensors, plugged into the first three channels of a NI 9402 installed in a NI cDAQ-9172 chassis (slot 5).  I've done plenty of analog signal measurements before but this is my first time trying to map a digital one.  I'm trying to measure the signal at the fastest possible rate (20MHz is what NI 9402 is capable of) and I cannot get the signal to record in any way that I could analyze it.  At this point all I'm looking for is a way to record the signal at 20MHz and look at a plot from the three sensors.  We're essentially just checking how quickly the signals are being sent to the sensors, so I need to be able to record it and zoom in to see all the 1's and 0's.
    I'm also doing this in signal express which may or may not be the whole problem.  To me it seems like a simple task, so I assume I'm just missing something obvious.  I got 3 digital signals, I want to record them at 20Mhz and then be able to look at the plots afterwards. I don't even want to really analyze them yet, just want to be able to zoom in and see the high's and low's from each sensor.  The test I'm recording takes about 7-8 seconds.  So far when I try this it looks like it reads the signal in the preview screen but if I try to look at the data afterwards there's nothing there to see. If anyone could point me in a direction to look or has an idea it would be extremely helpful.  If more information is needed I can get it for the board.  Thanks.
    -Tyler

    Hi Tyler,
    Are you pressing the Record button to log the data?
    Josh B
    Applications Engineer
    National Instruments

  • Measure Frequency of Digital Signal from DAQ-Board

    I'm using a National Instruments DAQ board and I need to measure the
    frequency of a digital signal from my data acquisition board.
    I know the measure frequency.vi (In diagram - data acquisition -
    counter), but i don´t understand yours implementation mainly in input
    "counter". Because i don't understand the relationship of board channel (for
    signal acquiring ) and the measure frequency.vi.
    Thanks in advance,
    [email protected]

    Hi,
       Attached is a vi which models your signal, and provides a way to measure the average frequency over a window of time. It converts the signal to a sequence of periods. I usually start with this approach because you can save the data in a much more compact form if your sampling rate is high. Obviously over a specified period of time, if there are no zero crossings the frequency is zero, so I was a little incoherent before. The real issue is the latency caused by averaging. Your frequency measurement is most accurate half your window size before the current time, so smaller windows give you more up to date measurements, but also more noisy. If you need the most up to date measurement, then you have to use the time since the last crossing which is the case where the frequency never goes to zero. That's probably not a realistic situation. If you needed less latency, you could use a prediction algorithm.
    Also, there are a number of signal measuring and processing vi's that LV gives you, for instance pulse measurements that could be used to partially implement this or other approaches, but I normally steer clear of them unless they fit exactly due to having to convert back and forth to the waveform data type.
    Have fun!
    Attachments:
    DigRandFreq.png ‏62 KB
    DigitalRandomFreq.vi ‏34 KB

  • Frequency of signal from anemometer

    hello,
    I 've to the output of an anemometer, an AC voltage whose frequency is related to the wind speed. unfortunately I did not get my signal frequency. I'm using the CompactRIO 9074 with NI9221 module. I see my good signal but I can not seem to extract its frequency. Have you any idea of VI? This is urgent.
    Thank you.

     Hi,
    I put a screen capture of the code as an attachment. I read my signal from the anemometer on the AI2 port NI 9221. For my range-measuring sensor, I have to measure frequencies from 0 Hz to 125 Hz. Documentation of the anemometer is attached too.
    Thanks
    Attachments:
    code.jpg ‏65 KB
    NRG40C.pdf ‏121 KB

  • Read/acquire signal from remaining empty channels of NI9205 by modifying the vi of ATI Force/Torque Transducer which uses the first 6 channelsof DAQ card.

    Hello,
    I am using force/torque transducer by ATI Automation. It provides me with its own vi to measure and write the data of the 6 signals (3 axes Forces, 3 axes torques)
    Following is my Ni system: -
    cDAQ 9172 chassis: Slot 5 - NI 9401, Slot 6 - NI 9205, Slot 8 - NI 9237. (Excitation voltage to the sensor/transducer (0-5V) using 9237).
    I connect the 6 signals from the transducer cable to channels ai0,1,2,3,4,5 in NI 9205(differential). The vi uses a calibration 6*6 matrix to finally display the calibrated voltage data.
    Now, I wish to use the remaining availabe channels that empty in 9205, namely ai17, ai18, ai19 for other signal measurements.
    ai17 channel is connected to Hall sensor  that gives out a square waveform corresponding to the rotor rpm. ai18, ai19 is connected to rotor-motor power supply's voltage and current signal respectively.
    But I am not able to access these 17, 18,19 channels from ATI company's vi. The vi loads the complete DAQ card (9205), uses only first 6 channels, hence the array data wire consists of only 6 channels. I can split these into 6 individual signals only.
    If I use a separate DAQ task to read channels ai17,18,19, then I get the error that this channels are reserved for some other task. Please tell me how can I access all the remaining channels apart from the first 6.
    I am attaching the vi here.
    Steps to run the "MEASUREMENT main.vi" : -
    Load calibration file:-  FT8840.cal;
    Load DAQ card: NI 9205
    Load ctr0 of NI 9401 (I am using this counter for rpm measurement purpose, this is my addition to the actual vi) 
    Attachments:
    DAQ - Copy.zip ‏574 KB

    There's nothing I can do to help.  I don't have your hardware to be able to modify your code and to set it up to make sure it runs properly.  Most people on the forum probably don't either.  This is where you'll have to put your programming and LabVIEW skills to work to solve your problem and make it run the way you want to.  If you run into a specific problem and get stuck, then please post back.

  • How to read and display a signal from my PIC Microcontroller onto Labview

    Hi,
    I am doing a project on a Pulse Oximeter and i am trying to read and display the signal from my PIC Microcontroller on Labview? How do i go about doing it? I am using the PIC16F877 and also making use of the USART?
    How do i implement and initialise the USART in PIC16? What are the steps to be taken, please guide me through the process? The link provides information regarding the USART connection, initialisting and stuff? Is it correct to use these codes in my program?Link: http://ww1.microchip.com/downloads/en/AppNotes/00774a.pdf
    Also, i am using the RS232 serial interface to connect to the PC? The connector i am using is the DB9 Connector. Which template and VI can i use? Am i supposed to use the NI-DAQmx and VISA? Also, for my USART connection, i am using the MAX232 Driver which is applicable for my application as i am working with +5V. So far, i have been reading and trying out on Labview and the steps i have taken are:
    1) Open a New VI and used the Instrument I/O(Read & Display) template?
    2) How do i configure the Instrument I/O Assistant Express VI to read the info from my device connected to COM1?
    3) I was reading the Labview Manual, 'Getting Started with Labview' and i was following the steps under Page 55, Communicating with an Instrument. Am i on the right track?
    4) How do i check and make sure that the port settings of the I/O Assistant and my PIC Micro Match
    Please help me out and guide me through the process. I am student at a polytechnic and i am very new to Labview and the software is used as a development tool for the project. I have a deadline to meet and i hope i can get a response as fast as possible. Your help will be kindly and greatly appreciated. I hope to hear from you guys soon.You can e-mail me all your answers at [email protected]
    Thank You
    Best regards,
    Ashwin
    Ashwin Kumar Mansukhani
    Attachments:
    Getting Started with Labview.pdf ‏901 KB

    Hi Ashwin,
    I am not familiar with the PIC Microcontrollers, but I am assuming you mean that you have the microcontroller sending out serial data that you want to read on another computer with LabVIEW. Please let me know if this is incorrect.
    What type of data is coming out of the serial port? Is it ASCII, or binary? The reason I ask this is that the serial communication in LabVIEW is done through a protocol called VISA, which uses ASCII data to send and receive. You can later convert this data into whatever form you need, but this is what it is designed to read and write.
    You can check the settings such as baud rate and data bits in a configuration utility called Measurement and Automation Explorer, or MAX. When you open up the MAX interface, you can expand the Devices and Interfaces entry on the left, and then expand the Ports entry to see your serial port. When you highlight this port, select the Port Settings tab at the bottom of the window, and you can see what the current settings are, and change them if you need to. You can also set these parameters in LabVIEW using the VISA Configure Serial Port VI.
    You can also test communication in MAX by right clicking on the correct port and choosing Open VISA Session. Then choose the Basic I/O light blue tab, and then go to the Read tab. When you click execute, it should read in what is coming from the serial port. This will allow you to verify that the correct information is coming in before even trying to acquire the data in the LabVIEW environment.
    In LabVIEW, the best resource to use the Basic Serial Write and Read example program that ships with LabVIEW. By examining the block diagram of this program, you will be able to see the basic programming flow of serial communication in LabVIEW.
    I hope this information was helpful! Please let us know if there's anything else we can help with.
    john
    Applications Engineer

  • I would like to tare (rezero) the input signal from a forceplate (glorified

    I would like to tare (rezero) the input signal from a forceplate (glorified scale) so that the base signal is set to zero, e.g.: a button on the front panel that resets the signal to zero prior to getting a measurement from a subject.
    We calibrate the force plate through labview and input our new equation into our scaling and mapping box which sets the signal to zero (or near zero) and the change in newtons (force reading) is accurate but when the application is closed and reopened the signal does not always start at zero (-400 to +1200 N), while the change in newtons is still accurate. I am NO engineer, I have Forest Gumped my way into getting some nice working VIs but I can't seem to find this function.
    Thank you very much for your time.

    Maybe that is the limitation of Acquire Input Data.vi.The vi can't identify the Unformal key.
    You can try to use Event structure and set to listen "key down" event.
    There are two terminals VKey, ScanCode will sent out the information when you press key.
    There are two pictures in attached file, 2.jpg will show you the detail.
    Good luck.
    Attachments:
    SpecialKey.zip ‏17 KB

  • Sequence 1create output digtal signal- 2 make microsecon​ds delay or less- 3 measure digital signal with board 6023e

    hello
    I need creat a digital signal and for this i use a counter output and then i need creat a delay after  a signal measurment and for this i use again a couter. My problem is how i can make this delay betwen create and measure a signal. this delay must to bethe shortest  possible  and precise. une of my attemps was make  a sequence and for make the delay i create a task for une virtual output with max frequency 5000000hz and just une pulse but i dont know how many time the labview get to go by the first task ( creat a output pulse and ent it) to make tis task before discribed to the last task (measure a digital sinal). Another thing that i dont know is how many time the libview get to create and eliminate une task. Une information beyond the kind of board (6023E) that can be useful to help me  with this problem is the information about my pc in this case i use a pentium4 3Ghz.
    thanks  

    ...My problem is how i can make this delay betwen create and measure a signal.
    ...how many time the labview get to end one task and start another one.
    What I tried to say is, that even if you use the counter of the 6023e-Board
    to create the delay and trigger the measure via LabView under Windows,
    you leave the realtime-path. Executiontime of LabView-code is then not
    determinated.
    One way to solve this, is triggering measurement via hardware and use LabView to read Data from the Buffer of the DAQ-card.
    You can find more info about DAQ in the "measurements manuall" of NI, delivered with your LabView Software.
    Lorand

  • Is it possible to use "Delay Values" to create a frequency signal from digital "Count Edges" -task? (= are the results I'm getting correct?)

    Hello.
    I have a digital encoder from which I need freaquency information (to ultimately get rpm -infromation). The problem is that this task is inside a loop with 2 other DAQmx -tasks that are using "one sample on demand"-aquisition mode and if I configure this new counter task to be a freaquency task, it only updates once in ~ second which makes the whole loop lag.
    I thus created an "artificial" freaquency signal by using "Count Edges" -aquicition mode and the "Delay Values" -block so that I substract the delayed signal from original "Count Edges" -signal. There is a 0,01s delay in the loop and I figured out that if the history of the "Delay Values" -block is 100 samples I would thus get the real edge-freaquency.
    I tested this configuration and the results seem to be at least really close to correct but I have no idea if this idea is in any way correct...
    This explanation was probably quite confusing so please see the picture attached.
    Thanks a lot in advance! 
    Attachments:
    are_the_results_correct.jpg ‏200 KB

    First of all, thank you for quick reply. Unfortunately I don't have the acces to the vi. until tomorrow.
    And yes, I think you understood correctly: essentially this arragement measures how many edges have been counted during one iteration. This is how I figured out that this could then be used as a frequency measurement:
    1. From the "Edges - Delayed Edges" I get the information on how many edges have been counted during last iteration.
    2. I "know" (really I don't?) that one iteration lasts ~0,01s because of the delay in the loop.
    3. There is 2048 edges in one round of the encoder so I get the rpm as follows: rpm = (edges - delayed edges)/204,8*60(s)
    (If I was using history size of one as you suggested it would be: rpm = (edges-delayed edges)/2048 * 60) However using history size of 10 and taking it account in the multiplication smoothens the response nicely.
    But doesn't this arragement count on the fact that the vi runs smoothly and there is no additional lag?
    I quess using another loop and notifiers for a dedicated freaquency measurement as you suggested could be worth trying. I just have to first learn how to use them. 
    If I do use them will the main loop run smoothly and not wait for every update of the notifier? This would be essential since the freaquency output refresses only about once in a second if I use the continious aquisition mode.
    Attachments:
    are_the_results_correct.jpg ‏198 KB

  • Analog signal from Laser Power Meter

    Hello,
    First, I have to say that I am new using Labview.
    Probably for some of you the question I am going to ask is pretty easy, hope you guys can help me solving this.
    I am trying to acquire an analog signal from a Fieldmate Laser Power meter, the specifications from this meter are shown in the link below:
    http://www.coherent.com/downloads/FieldMateDataSheet.pdf
    I need to get the signal and save it in MS Excel files. My big issue is with the acquisition of the signal from the meter to the NI Board. I am using an NI SCB 68.
    Hope you guys can help me.
    Thanks.

    The SCB68 is just a shielded connector block, not a DAQ device.
    Use NI's MAX utility (Measurement & Automation Explorer) to find out what DAQ card you have installed in the PC.
    There are also plenty of analog acquisition examples that ship with LV, Search Examples in Help.
    -AK2DM
    ~~~~~~~~~~~~~~~~~~~~~~~~~~
    "It’s the questions that drive us.”
    ~~~~~~~~~~~~~~~~~~~~~~~~~~

  • How to read a continuous temperatur​e signal from a Pyrometer via RS-232

    I'm trying to read and graph a continuous signal from a Pyrofiber Lab pyrometer which is coming in through an RS-232 cable. As far as I can tell there are no device drivers for this instrument (or any other pyrometers). 
    If I have the pyrometer take single measurements I can get those into LabView using the Instrument I/O Assistant, but only as an ABC string reading " 'emmisivity value' 'temperature' 'corrected temperature'" and not as individual numbers or data that I can use/graph. If I have the pyrometer in High Speed Transmit mode (which is the mode I need it in), I can't read the signal at all. How can I get LabView to continuously read (and record or graph) the incoming signal? And is there some way to parse the signal when it comes in as a string with " 'time' 'emissivity' 'temperature' 'corrected temperature'"?
    I'm very new to LabView (and programming in general), so any hints on a good starting point would be appreciated. 
    Solved!
    Go to Solution.

    progers - There is not a specific solution, as there is not a device driver for this device (assuming you are also using a pyrometer).
    There are serial communication examples in LabVIEW, by going to Help >> Find Examples >> Hardware Input and Output >> Serial. 
    You will need the programmer's manual for the device to know what serial commands to use to talk to the device (see Dennis's post above).
    Best Regards,
    K. Anderson
    Applications Engineer
    National Instruments

  • How can i use labview to acquire temperature from optical fibre sensors

    i am trying to develop an application that would enable a user to acquire temperature data from optical fibre sensors and display the profile on a PC screen but i have got no clue of how to go about it

    To provide some assistance, I will need to know:
    1) What type of output does the device produce? (volts, current, frequency ...)
    2) What type of conditioning does the signal require? (gain, filter, excitation, bias resistors ...)
    3) What type of calibration does the vendor provide? (how the output signal relates to temperature)
    These characteristics have already been determined by the manufacturer (or the engineer who developed the interface electronics).
    You have made no mention of the computer, OS, software, or hardware you will use. I could try to walk you through the selection process; however, I would probably take up too much space trying to discuss all of the possible combinations.
    Could you provide some additional information about hardware and soft
    ware you will use? I will look for a response.

  • Can I measure the frequency from all PFI pins?

    I am using a PCI-6229 DAQmx card. I am trying to measure the frequency from pin PFI 5. I have been successful in measuring frequency from PFI0 and PFI1 but for some reason I am not able to measure on other pins. When I run the run the DAQmx Read sub VI it times out like it is not reading anything. I am using the same sub VI I created to measure 5 as I did 0 and 1 so I know that the VI is working. What is the matter? Are there only certian pins that I can measure? Would the sub VI time out because there is no signal on the pin?

    Hello Flowserve1,
    Thanks for your post!
    The basic answer to your question, "Would the sub VI time out because there is no signal on the pin?", Is yes if there is no signal coming into the pin your are bring a signal in on. It sounds like you were able to do a "frequency" measurement on PFI0 and PFI1? Usually the counter tasks are used for such a measurement. How are you performing these frequency counter tasks on your PFI lines? It looks like on the pin read out that PFI0,1 and 5 are for digital tasks and PFI routing lines. Are you internally routing your signals to other places? If you want to measure the frequency using counters, this board has two of them so use Ctr 0 and 1 gate or source to make these measurements. Let me know if any of this helps you and perhaps you could post a piece of your code that you are using to make your frequency counts.
    Cheers!
    Corby_B
    http://www.ni.com/support

  • Find the depth of head from the kinect sensor

    Hi,
    I'm trying to get the actual depth of head from the Kinect sensor positioned at 82 inches from the floor and tilted to 40 deg angle.  I used Skeleton Joints head point and right angled triangle trigonometry but unable to get the accurate measurement.
     I considered Joint[JointType.Head].Position.Z as distance but when manually measured the value is not accurate, why it is different from the manual measurement.
    Any help would be appreciated!
    Mani

    Body tracking provide estimates based on body tracking algorithms. These take into account the some offset into the head to represent but based on angles and noise and tracking state of the joint you may need to average it out. Also, you can take the point
    as a starting point and then analyze the actual depth data and calculate your own if you need better accuracy.
    Carmine Sirignano - MSFT

Maybe you are looking for