about precision DAQ assistant

Similar Questions

• Precise triggering voltage input and output generation in the DAQ Assistant

  Hello

  I wonder if anyone has come across a simular problem with the synchronization of input and output voltage. I use a box 11 LabView and NI USB-6259. I have been using the DAQ Assistant to configure the input and output channel. In particular, my task is to generate a single rectangular "pulse" as the output voltage to drive a coil and once the pulse went to get a signal from a sensor of magnetic field and get a power spectrum. This means that the order and the time during which the DAQ Assistant is used is extremely important. For example, the output voltage channel must be opened first for 2 seconds. Subsequently, the channel of input voltage must be open for 1 second, in which the sensor signal is obtained and post-processed. Only after these tasks are performed in this order he can can be repeated in a loop until the experiment is over. I don't know how to trigger data acquisition assistants (one for entry) and the other for the voltage output correctly. Y at - it a trick?

  See you soon

  Michael

  Hi Dave,.

  Thank you that I wired the error strings but the timing issue was unrelated to it. In the DAQ assistant, I simply had to choose the continuous aquistion of the 'samples' methods 'N-switch' for input and output voltage and all works fine now.

  Thanks again

  Michael

• Missing DAQ Assistant

  Hi guys,.

  I have LabVIEW 2015 and 14.0 DAQmx.

  Yet, the daq assistant is absent the express--> palette entry.

  Any help?

  Message 5 of this thread will give you the answer.  More precisely

  DAQmx and LabVIEW version compatibility

• DAQ Assistant acquires the data into segments

  I'm writing a code that reads and records the voltage, temperature and pressure on a cdaq-9174 using or 9221 and cards or 9173.  The problem is that when the daq assistant is set to N samples outputs the data blocks in the graphics.  I wish it were a continuous stream so I can see what is actually happening.  I tried to change continuously, but it gets an error or is has data about 16000 points in 10 seconds, which is a lot more that I prefer.  The code I am using is borrowed from another person and then the installation exactly it works on this computer, but not mine.  Does anyone have any suggestions on how to solve this problem.  I enclose the code as well as the sub live he uses.

  Thanks for all the help.  I didn't know at first that the NI 9237 card has a minimum sampling rate of ~ 1600 Hz.  I am now able to taste to 2000 Hz then use decimating continues to write in my file at 200 Hz.

• Conversion task DAQ Assistant

  When I try to convert my DAQ Assistant tasks with a right click - Convert to task NOR-DAQmx I get a name and a scrolly input output with all the broken wires. Similarly, if I create a task in MAX and then use a constant for the task on the block diagram name I get the same result of entry scrolly. Am I missing a step here?

  Thank you

  Hi Mirabelle

  Glad to hear that you managed to solve the problem! In response to your questions:

  -L'information that read you about the creation of tasks in MAX is correct; It is possible to create a global task (an available screw a lot) in MAX. However, it is not necessary to create all of the tasks in MAX. As you think, if you use the task within a single VI, there is no need to create the task in MAX - in fact, it's probably easier just to create the task in the VI himself, either with screws of Express Assistant DAQ or DAQmx screw person on the range of functions located under e/s measurement > DAQmx - Data Acquisition.

  -When tasks change in MAX, it will not automatically be changed in LabVIEW. To make changes in LabVIEW, you will need to edit the task properties in LabVIEW, or remove the old task and replace it with the change.

  -I'm not sure what you mean by the question in your "P.S." to 100%, but I'll try my best to answer. Is there a specific example you speak? If you ask the use of screws DAQmx as DAQmx Virtual Channel Create, task control DAQmx and DAQmx Read etc., as shown in the examples of the expedition, then there are a few reasons to use those. Basically, screws of Express DAQ Assistant consist of a combination of the screw in the DAQmx - Acquisition of data from the function palette section. In general, screws of Express DAQ Assistant moving slower than the standard SIE DAQmx. It may be easier to debug the code when using standard screw, as it is obvious which task runs each section of the code. And finally, there are some limitations to the use of the DAQ Assistant, so while they may be easier to use in the short term, long term, I would recommend familiarize themselves with standard screws, because they make possible more complex tasks.

  I hope this helps! Feel free to let me know if you want to bring me anything, or if you have anything else that I can help you.

  Best regards

• DAQ Assist reading bad voltage

  Hello

  I use the DAQ Assistant VI to read a voltage analog input of a card of National Instruments PCI-6221. I read the AI0 pin voltage. I provide voltage directly on this pin of a continuous feed, but the measurement of voltage obtained from the DAQ Assistant is incorrect: it seems to be reduced by a factor of about 1/3. For example, if I have 4 volt power to pin AI0, DQA help bed 1.43 Volts. I used a multimeter to confirm that the voltage on the PIN AI0 is actually 4 Volts and I know that the problem is with my LabVIEW program and not my diet.

  Here are the steps that lead to my problem:

  1. in the block diagram, I insert a block DAQ Assistant.

  2. in the Properies of the DAQ Assistant, I select an analog input-> voltage

  3. select channel ai0

  4. I click "test" to test the channel

  5. the tension is indicated as being 1.43 Volts, although 4 Volts is provided to pin (this is confirmed by a multimeter).

  6. to ensureI click OK to complete the configuration of the DAQ Assistant. I run the program and draw blood. The graph also 1.43 Volts.

  Does anyone have an idea why this can be produced. I have spent a good 4 hours trying to diagnose this and haven't found anything.

  Thank you

  Alnaif adnane

  It's normal. Do a search for the topic "ghost".

• DAQ Assistant as a selector of case

  Hello

  I'm reading an entry to my daq assistant digital camera, and then to hold for x number of seconds, up to that time. The entrance to the wizard matter not after the first entry.

  So, I used a switch case and started trying with a virtual switch. Everything worked fine... until I begin to try with the daq assistant. The output of a data acquisition assistant is a table 1 d of boolean. The entry for the case selector is a Boolean value.

  It is possible to select the cases according to the output of the daq assistant? If it is true, how can I do this?

  Greetz Margaret

  I added a table of index to your code that modifies the array to a single digit. Remember that this only gives you the first digital input. If you switch to a different channel, you'll have at this table to a different number of the index.

  Second time isn't a very good way to measure time so I changes the way vi a measure of time.

  Thirdly, the outside while loop is not necessary. The two loops will be run until you press the stop button. I think about the use of an event to capture the stop function so that you don't need to a stop button.

• Is the DAQ Assistant compatible with LabView7?

  I am equipped with a LabView7 and a NI DAQ - 6015 Pad and am trying to monitor the temperature with two thermocouples. I searched some tutorials online, but most suggest using assistant DAQ, which is not listed in the section of my functions palette entry. I have downloaded the NOR-most recent DAQmx driver who is supposed to be compatible with LabView 7.x. I don't know if this means that it is compatible with LabView 7.0. I still do not see the DAQ assistant appear.

  Any help or suggestion (about DAQ assistant or how to program in LabView7 to solve my problem) is greatly appreciated!

  Thank you.

  It looks like the DAQmx latest version is 8.1 which will work with LV 7.0

  See here http://digital.ni.com/public.nsf/allkb/97D574BB1D1EEC918625708100596848

• Question of sampling DAQ Assistant

  Hi all

  I have attached a VI that I used to record data from a few different voltage and the channels of the strain. All channels and sensors work perfectly and the VI reads data very well, but will be only newspaper for about 9 seconds. I found that the reason is that, within that period, the amount of updated read samples is reached. I also found that the reason for which is rather than on the statement sampling DAQ assistant 50 or 100 Hz it samples at a rate of about 1.6 kHz (0,000620 seconds). I have nothing seems to change the rate of that sample to so if anyone has any ideas it would be much appreciated!

  Thank you very much

  Andrew

  I think I can explain what is happening. In a previous post, the op mentions using a 9237. That has a sampling rate minimum of 1.63 kech. / s. The rate in the corresponding file.

  Andrew,

  Read the Manual would have answered your question.

• DAQ Assistant as input for the formula

  I need the output to my DAQ assistant for that entry into a knot of formula. But I can't do it because the terminals are different; data Dynamics vs double [64-bit real (precision ~ 15 digits)]. Is there a way in which I can use these dynamic data in a node form?

  Look in the express palette under the manipulation of signal for an another express VI, called "DDT".

• Using the DAQ Assistant. can I create a VI that measures continuously during a fixed time?

  I use LabView to an NI USB-6009 enclosure, with two accelerometers like my analog input. When you use DAQ Assistant to build my VI I have not seen an option to measure continuously for a set amount of time. I need the test to run for two seconds and then stop.

  Is there anyway to specify the exact duration of each test?

  It's about as simple as you can get. Set the number of samples to be twice the sampling frequency (or whatever the multiplier that you want). That's it - a simple DAQ Assistant and nothing else on the block diagram. If you need it to be variable, just wire a control of the number of input samples.

• is daq bit resolution applied to the area defined in the daq assistant or well to the limits of physical blood of the daq hardware.

  Hello, this is my first post here,

  I've been wondering about this:

  When you configure a new daq with the daq Assistant, is the resolution applied to the voltage / number of entries you define, or is it a fixed value per volt by channel.

  For example:

  I have a 6015 usb data acquisition, it has 16 inputs analog, 16-bit resolution 250 kech. / s 09:50 volts.

  so is this as (2 ^ 16) / (16 * (-10-10)) = my resolution through volt?

  or that this has nothing to do with the amount of channels,

  If I want to measure more than 0 to 5 volts, my 16-bit apply from 0 to 5, or even more scale of data acquisition (which is 09:50 volts)

  Thank you

  Marco

  You will get full-resolution 16 bits on each channel regardless of the number of channels is configured.  Renault most are multi-plexed if your specification of sampling RATE in usually a global significance that you can only scan channels with a sampling frequency = MAX RATE / number of CHANNELS.  Also, most NI Renault have a Programmable Gain amplifier on the front-end server, so if you specify a range of voltage smaller in your task configuration the amplifier will automatically increase the gain to use most of the possible BIT ADC.  You see care device and for more details...

• How to parse the input data of several channels simultaneously via an NI USB-6251 box by use of a single DAQ Assistant?

  I did separate VI for reading signals from several channels on a map of NI USB-6251.  I would like to combine these in a VI VI alone so that they can run that at the same time, however, there is an error if there is more that a single DAQ Assistant in the same--> error-50103 VI was held at DAQmx controls Task.vi:32 (the specified resource is reserved. The operation could not be performed as indicated.)

  All the inputs of channel must then be read in with a single DAQ Assistant, but all of the data on different channels are not separated.  Can save this data in a matrix or otherwise manageable which allow to facilitate the analysis of the data from the separate channel entries?

  I tried to view the data in a file of measures, but then when I tried InPort data, I could all the data I wanted.

  Hi AggieGirl,

  Good afternoon and I hope that your well today.

  First of all, you will not be able to have more than one DAQ Assistant by input analog or analog output task because the device has only one of each. So, you must have a DAQ task to HAVE and AO. (This is not the case for DIO static).

  There is far from split signals using the express VI - signal splitter.

  When you say you saved this file and it does not work, how it did not work? The Express VI - save a file of measures needed to manage multiple waveforms. Can send you your code & explain more about what was not OK on the file?

  

  Thank you

• Disadvantages of using DAQ Assistant

  I need 2 analog inputs continuously at 5-10 kHz from the sample and then use a combination of producer consumer and State Machine for the processing of data in real-time.

  In most parts of the example I've seen, people always use Subvi of data acquisition groups. Even though I know how to set up getting data using the Subvi, I like to use Express VI DAQ Assistant to perform data acquisition.

  Known disadvantages of the use of VI express in my case (see 1st line)?

  With the help of an express VI will slow down time of execution and, therefore, your time of iteration of loop due to the fresh general partner.  If you are concerned about the timing of your program, then you should strongly consider using the DAQmx API screws.

• DAQ Assistant is not in LabView

  Hi all

  I use NEITHER cDAQ-9174 and NI 9203.  I have already installed the driver for the NI 9174 cDAQ, which is NEITHER-DAQmx 9.8.0.  I can see the device when I opened NI MAX. However, when I open LabView 2015, I can't find DAQ Assistant in the function Palette. I noticed on the chassis, 'ACTIVE' light is not on while two other "POWER" and "READY" light is on.  I look in the forums OR but I can not find the solution.

  Any suggestion, please help!

  Thank you!

  DAQmx 9.8 is not compatible with LabVIEW 2015.  You must use at least DAQmx 15.0.  See here for more details: NOR-DAQmx and LabVIEW compatibility