Erronerous offset in AI data on all channels
Hello!
I'm using NI-6152 PCI multifunction DAQ card with BNC-2120 accessory. MAX using DAQmx 7.3
Up to now everything was OK. Today I have started the measurements and found the shift of the AI results on about 1V up. Then I have switched off all BNC from accessory, connect AO0 to one of the AI and through test panels in MAX apply 0V to AO0. Then measure the AI voltage on that channel and see ~1.2V. Such result is independent from the AI and AO channels used. Also, I have tried also apply sine output with the same result. Anytime I seen shift of resulting voltage up.
I have tried reset device, self-test and internal calibration with no efects. I also tried to use another BNC block.
In which can be such problem? DAQmx, device, bnc or cable?
Is it possible that self-test does't detect some damage of the device?
Thank you for response!
I have tried a lot. First, I have used another generator. Second, I just connected both + and - of channels to AI ground and have same result on input. Also, I have tried generator on the BNC-2120. So, the problem is in Analog input.
About self-test: OK, I see, but the board also passes self-calibration successfully with no changes. That is more strange. Seems that internally board should measure voltage correctly... I have also tried to reset calibration to default external calibration (we have never done a external calibration by ourselves but only self calibration). Also with no result.
Also, I have reinstalled DAQmx and board completely.
One that I found additionally is that the offset is dependent upon measurements regime: differential or single-ended. In single ended regime this large offset remains, but is of opposite sign (about - 1.1 V).Message Edited by Baturin on 04-12-2005 11:37 PM
Similar Messages
-
Acquiring data from all the analog channels of NI-3202 NODE using a single sensor
Hi all,
I would like to know that can i be able to get the data from all the four analog channels of NI-WSN node 3202(analog input node) connecting only single sensor on the analog input and connecting all the remaining analog inputs using wires and also shorting the ground pins corresponding to each analog input pin.
By configuring the each channels like 0.5 sec delay for every analog channels to acquire data. can we get the sensor data from all the channels by doing this. basically here i am trying to increase the minimum sampling rate of the ni-wsn NODE 3202 which is 1s.
I this approach is correct or we cannot do this.
ThanksStefan,
In terms of differential and RSE, channels 0-8 should default to differential when using test panels. Differential needs two input channels to function correctly and these channels must be spread apart by 8 channels. (i.e channels 0 and 7 are a differential pair) Channel 13, on the other hand, will default to rse if chosen as the reading channel because there does not exist another channel that is eight away. I am not quiet sure if the virtual channels will default channel 5 into being differential but I will check into it. If it is differential as default then you may run into problems since channel 13 is utilized in both strain gauge reads.
"The second question is, if we can also use the "voltage" setting for measuring strain gauges? we did that in the past, using LabView 6.2."
If you are referring to "voltage" as acquiring a signal with custom voltage with exciation then I would reccomend using example in LabVIEW called Acq Wheatstone Bridge Samples (with Calibration). This can be found by navigating to LabVIEW's example finder and expanding Hardware Input and Output>>DAQmx>>Analog Measurements>>Strain.
I have also included some useful links that may provide more insight into the SCC modules as well. Also, what is the excitation voltage and power that your strain gauges are expecting?
SCC Tutorial Series: SCC-SG0x
SCC Example Series: SCC-SG0x
Using the SCC-SG11 Shunt Calibration Module
Thanks,
Gio L.
Digital Support - Product Manager
National Instruments -
Let all channels(with same data structure)run one program
Hello,
I want to let all channels with same data structure run one program,how can i program it?
Thanks!Hi charleen,
You're going to need to provide more details for us to help you. In general "channels" do not "run" programs. You can, however, run a program which loops over channels, checks their properties, and decides whether to include them in the overall analysis. What do you mean by "data structure"?
What do you want to actually happen in the "program"?
Brad Turpin
DIAdem Product Support Engineer
National Instruments -
i am acquiring 32 channels thermistor data (temp in degree vs date/time) in waveform plot using array to cluster function ,
now my problem is how to write this data into xls file for all channels continuously.
please help me at the earliest & i am new to Labview.Hi Priyanka,
Writing to excel file continuously is not a good idea, you can use ".CSV" or TDMS file format and once data acquisition is completed you can convert that to excel file using report generation toolkit.
With Regards
Miraz
Kudos is better option to thank somebody on this forum -
Processing acquired data (8 simultaneous channels) in RT host (producer,consumer problem)
Hi Gents,
I have a Crio 9024 and two delta sigma modules NI 9234, I have to acquire 8 cahnnels simultaneously at 51,2 kHz from FPGA and transfert this data via DMA fifo to the RT host for proceesing (FFT for all channels and send data to a host computer via a stream network). I succeed to do this with 25,6KHz as sampling frequency but when I tried with 51,2KHz (my goal) I had problem because in RT code I have a producer loop receiveing data from fpga (DMA fifo) and sending this data to a consumer (Queue) loop in RT also for processing this data but the producer is to fast so the consumer loop can't proccess data in time and the queue is overflow. I have replaced queues with RT fifo,single process variable,... but no luck !!!
Any way how to send 8 channels data from one loop to other for processing (base band FFT N channels) at 51,2KHz ???
Please I need help !!!DMA Fifo:
To avoid overflow you have to configure the RT side which has a default size of 10000 (Rio4.0 and above 2^14 elements) or doubled FPGA depth (fifo_config)
RT Fifo:
config example
Read data from DMA to RT Fifo
(read all elements available and write this data block to your RT fifo, which is configured to hold n-Blocks of size x, i.e. 300Blocks of 18432elements each)
--> here I suggest to read a multiple of 8, because of your channel count
Read data from RT fifo to stream
(send data blocks to the host where each block is one element in terms of streaming buffer --> configure streaming buffer)
Configuring large RT Fifo's has an impact on memory usage, so have an eye on it.
Screens are just examples (not functional code)
Hope it helps
Christian -
How to transmit counter input data of different channels simultaneously?
Hello.
I'm using X-series PCIe-6361 DAQ board which have 8 DMA channels and Labview 8.2.1. I upgraded the version of DAQmx as 9.0 which supports the X-series devices and confirmed the board worked normally on my system.
I'm trying to measure the pulse width continuously from 4 different pulse trains with CMOS level. The frequencies of signals are same but the pulse width and phase are varying with respect to time.
http://zone.ni.com/devzone/cda/tut/p/id/9376
From the tutorial page of NI X-series, I saw the following expression "X Series also includes eight DMA channels to stream data directly
between the device and PC memory without CPU interaction or additional
programming effort. These eight channels provide parallel data streams for the analog I/O, digital I/O, and all four counter/timers."
But when I started the Labview programming, I realized that the counter functions of different channel cannot be put into a single task. So I couldn't help but separate the read functions into 4 individual tasks and there are timing differences in data transmission between channels up to 250 micro-sec because of the sequential running.
How can I eliminate the timing difference and realize parallel data streams for the counter?Check out these links. I hope that they help!
Fieldpoint and RT
Logging Data with a FieldPoint FP-20xx to View in a Web Browser
Transferring Files from a FieldPoint FP-20xx through an FTP Server
Introduction to Using DataSocket Commands to Communicate with FieldPoint Etherne
t Network Modules
Good Luck!
Mike
NI -
DIAdem 2012 displaying all channels as "Noname" for .tdm files
Hi
I'm experiencing a problem with DIAdem 2012 when opening .tdm files.
I've reinstalled all NI software components, and still the problem remains.
All channels are displayed as "Noname", "Noname_1" etc.
Even worse, all values are displayed as either "0" or "NOVALUE".
See attached image for example.
The attached image is displaying the "Example.tdm" file which is opened by default when starting DIAdem.
When opening the "Example.csv" file the problem is not there (channels have names such as "Time", "Velocity" and values).
So what could be the problem related to reading/loading .tdm files? (Note, as I said, I just reinstalled DIAdem from scratch)
Attachments:
DIAdem_noname.jpg 270 KBHi salte,
"TDM_DataPlugin" is the default name that the ASCII DataPlugin Wizard would give to a DataPlugin you or someone else created to open files with a "*.tdm" file extension. I'm betting that's where it came from-- the behavior you see in the Data Portal is also consistent with loading a TDM file as if it were an ASCII file. DIAdem does not install this DataPlugin, and I highly recommend that you remove it.
To remove the DataPlugin, go to the DataPlugin dialog, select the the "TDM_DataPlugin" in the list, and hit the red "X" icon or the <Delete> key on your keyboard. To get to this dialog first start in either the NAVIGATOR or SCRIPT panel, then depending on your DIAdem version select one of the following two menu paths:
"Settings >> Options >> Extensions >> DataPlugins..."
"Settings >> Extensions >> DataPlugins..."
Once you've removed the "TDM_DataPlugin", you will again be able to drag TDM files from the NAVIGATOR tree view into the Data Portal.
Brad Turpin
DIAdem Product Support Engineer
National Instruments -
Export all Channels to Excel without a dialog or a stp file
Hello,
i try to write a vbs script that export all channels that exists to excel without a dialog. By the reson that i don´t know exactly how many channels are generated while the measurement i can´t use a stp file. I tried to set all variables but everytime i get a global error (excelstat=100).
Since this problem was discussed in 2006 ( http://forums.ni.com/ni/board/message?board.id=60&message.id=2115&query.id=95137#M2115) perhabs there is a solution now with Diadem 10.2, besides generate the stp file in the script or hold stp files for any possible number of channels.
Thanks for the help
diademi
Message Edited by diademi on 04-24-2008 10:10 AMHi diademi,
Nothing has changed in DIAdem since then, but you do have several options. First and foremost, you can save the data as a TDM file and use the freely downloadable TDM Excel Add-in to load the TDM file into Excel. This has the advantage that it's extremely fast but the disadvantage that it's completely inflexible as to where and how the written values show up in Excel.
http://zone.ni.com/devzone/cda/tut/p/id/4906
If that doesn't work for you, you can export the data channels into an ASCII file, as mentioned in the older link. This has the advantage that it's fast but the disadvantage that it's not very flexible as to where and how the written values show up in Excel.
Finally, you can export your data channels into an Excel file using ActiveX calls in a DIAdem VBScript. This has the advantage that it's flexible in where and how you write the values, but the disadvantage that it's comparatively slow, especially for large data sets.
Let me know what sounds most promising, and I'll send you code. Also, please confirm whether you're using Excell 2007 or an earlier version.
Brad Turpin
DIAdem Product Support Engineer
National Instruments -
Hi, in my project we need to send messages(PGNs) of J1939 format onto the microcontroller device and receive the response from the same. I have tested the microcontroller with the NI CAN software using MAX and it is working fine. Now I have to develop a LabVIEW application to send and receive the commands. I have used the "CAN write.vi" (Channel API) to send the CAN message. By using the "CAN Create message.vi" I am able to configure the PORT, Arbitration ID, Data length (8 bytes in my case) etc. But I dont find the field where I can fill in my data (8 bytes) in hex format. Presently I have put my data in the "Single-chan Signle-samp dbl" input field of the "CAN Write.vi". Please let me know where I need to fill in the data values.
I have attached the vi I have developed.
Regards,
Krishna.
Attachments:
CAN_Test.vi 92 KBHi Kittamma,
You wrote, that it worked with the Max and now you are using the create channel function. Is there a reason not to take the channel database? To have control about every databyte, the only solution is to create or have one channel for every databyte and to write all channels together in one task. The data has to be wired allways to the write VI.
But keep in mind, if you have allready a databasefile or configuration in MAX, you can take the Init or InitStart VI and this VI takes the configuration automatically from MAX or your file.
DirkW -
I am working on an audio player that will take a parameter
from a web page and play the appropriate MP3 file. Each page in a
series of pages calles the same movie. It works but I have a
seriouis problem with the code. If the user navigates to the next
page while the current page is still playing the audio, the new
audio is played on top of the older clip. I suspect that each time
the same movie is called, a new SoundChannel object is being
created.
I'd like to come up with a function to search all current
objects that are not in the display list and issue a Stop command
to all existing SoundChannel objects.
Does anyone know if it is possible to write a function to do
this? Have you written such a function? I can't come up with any
other way to stop the currenlty playing audio automatically. I
can't rely on the user to stop it manually...
The SoundMixer.stopAll(); doesn't work, I've tried it. :-(
TIA
Peter H.Peter,
> Finally, I have a function to play the sound with a
line:
>
> _channel = _snd.play(_pausePosition);
Everything you've described sounds fine. For what it's
worth, you don't
actually have to wait until the sound fully loads before
issuing the
Sound.play() method (the sound will progressively download,
which means it
starts playing as soon as enough data have loaded) -- but
again, your
description so far sounds just fine.
> I suspect that each time the SWF is called to play
another
> MP3, the code is creating another Channel object and
> playing the newly requested MP3.
This is the part that puzzled me at first, but now I think I
understand.
What I missed in my first read-through was that the new page
starts playing
while the initial page is still open. That means there are
two instances of
Flash Player running, each with the same SWF, but a different
parameter.
Even though both instances of Flash Player are playing the
same SWF, each
instance comprises its own unique world. You can't (easily)
enumerate the
objects in both SWFs in a collaborative way, because they're
separate
entities -- twins, if you will, but still unique human
beings.
> Specifically, I was thinking that if I had a way to
identify
> all Channel objects instantiated within this movie, I
could
> just do something to unload them all from memory to
> ensure none were already playing.
By the looks of it, each of your SWF instances, across
x-number of HTML
pages, has a single, named SoundChannel instance: _channel.
So it isn't as
if you really have to search for instances -- you know them
at this point --
it's that you have to get separate SWFs to speak to each
other and figure
out who needs to keep mum.
Off the top of my head, I can imagine using JavaScript to
feed a second
parameter to the SWF that a given page opens. The first
parameter, of
course, is the MP3 to play. The second parameter could be a
timestamp.
This way, each page has an "age," and you could feasibly
communicate from
SWF to SWF with instructions that only the youngest SWF be
allowed to play.
Inter-SWF communication happens with the LocalConnection
class. You set
up an arbitrarily named line of communication, then "listen"
to that line.
SWFs can also send messages over one or more lines. See if
that gets you
started, and be sure to come back if you have additional
questions. I'm
interested in this topic myself now, so I'll try to work up a
proof of
concept on my own and we can swap notes. :)
David Stiller
Adobe Community Expert
Dev blog,
http://www.quip.net/blog/
"Luck is the residue of good design." -
CRIO 9025 Data Logging (128+ Channels at @ 1000Hz)
Hello,
I have the following configuration:
(1) cRIO 9025 controller on a NI 9118 8-slot Virtex-5 FPGA chassis, loaded with AI/TC modules
(2) NI 9144 8-slot EtherCAT expansion chassis connected to the 9118 via EtherCAT, loaded with AI/TC modules
I have been tasked with recording data on ALL of these channels at 1000Hz. I have been toying with various types of software architectures and cannot come up with an optimal system. I would like to log data directly to the cRIO 9025's on-board storage (and later retrieve via FTP).
What is the best way to approach this? What type of architecture should I be using?
Any help is very appreciated. Thanks!Hi SR,
Unfortunately, you won't be able to daisy chain multiple 9024 controllers. As explained in this Developer Zone article, you can use a 9024 as a master with a series of 9144 slave chassis. If you're using multiple 9024s, you'll want to put them on on the same network and write a master application that communicates with all of the systems. Hope that helps.
Andy H.
National Instruments -
Where's the limit? Assume a new Dell Latitude running NT with 128 MB RAM and a fast P3. Equip it with the DAQCard-AI-16E-4 connected to an SCXI chassis with 2 SCXI-1125 modules.
How fast can I run the sample rate (per channel) if I want to do continuous DAQ on all 16 channels while computing the power spectrum of all channels once per second (using one second's worth of samples)?
The DAQCard has a tiny FIFO, and I'm hoping to use pretriggered scans so I don't have to wait for data. Is that an option without the DMA functionality of the PCI E-Series boards? Without it I will have to constantly empty the FIFO into a "software" b
uffer which will cost boku (many) processor cycles, correct?
So what say the experts... how fast can this thing run? How about if I ditch the laptop and go PXI with the whole deal? Lets make the case!
Thank you!I believe the PCMCIA interface is going to be the limiting factor in this case. The maximum continuous rate for a DAQCard will vary from computer to computer, but it isn't extremely fast.
Being optimistic, let's estimate 64 K samples/second. I don't know if this is high or low nowadays, but it is higher than I could ever achieve a couple of years ago. Divide that by your 16 channels, and you have 4K blocks. I think you could process this in 1 second easily. This gives you 1 Hz resolution up to 2 Khz.
Now, if you ditch the laptop and go to PXI, it is a whole different story. DAQ rates will not be the limiting factor. You just need to find out how large of a block you can process and keep up.
My approach to this problem would be to figure out what analysi
s you need, then figure out what hardware can accomplish it. Do you really need 1 Hz resolution? Do you need to process every bit of data that comes in? Are you going to store the results, or just display them on the screen? Can you do post-processing of the data if necessary?
Bruce
Bruce Ammons
Ammons Engineering -
Hi All,
From the field I have 28 channel sensors data, the data rate is 10KS/S for each channel.
I have to store field data upto 3 Month to generate the historical reports or to analysis the field conditions.
The data is very huge so i want some suggestion from you all to store this much of data techinique or prefered way to store this much data.
Thanks and Regards
Himanshu Goyal | LabVIEW Engineer- Power System Automation
Values that steer us ahead: Passion | Innovation | Ambition | Diligence | Teamwork
It Only gets BETTER!!!
Solved!
Go to Solution.Thanks for your suggestions.
The project requirements are already define by the costumer. The costumer wants complete 10K data of all 28 channels. He can't afford the less sample rate or data loss.
I tried with TDMS file to store 10 KS/S (SGL Format) data for 28 channels(Sine Wave); the file size is around 3.5 GB for 1 hour. The complete day data come around 84 GB, I am not sure about the TDMS file size this can support upto this much of file size, if this not support then again I have to save complete day data in set of bunch of TDMS files. Now if costumer want to see complete 1 hour data report in graphical or tabular format the task to perform the action takes around 2-3 minutes or some time it come up with some error like "Not Enough Memory". So in the end of the day if user want to see the complete day report how I can provide the report that have such kind of huge data.
I am using PXI RT system with some local hard disk. The PXI always have 7 days data as an backup or in case of connection failure with server the data backup is in PXI.
So my issue now same what database or file format i have to chosse to store complete data.
If there is any techinque to compress the data please suggest me.
Thanks and Regards
Himanshu Goyal | LabVIEW Engineer- Power System Automation
Values that steer us ahead: Passion | Innovation | Ambition | Diligence | Teamwork
It Only gets BETTER!!! -
Plotting the best increasing dynamic temparature data from several channels
Hi All !
I want to plot dynamic temparature data in real time. I have 8 sensors to acquire signal through USB. I want to plot the best increasing signals amaong them. How Can I do this?
I can plot all of them togather but not getting the clue how could I choose which has the increaseing profile and discard those which does not have any temarature increase.
Should I need to store the data first and then do some gradient masurement on those or any other method?
But still do not know to make gradient masurement on dynamically acquiring data..
Thanks and Regards,
HasanHi Hasan,
There are probably many ways you can do this. First of you probably need to convert the data from dynamic data type to waveform or double. If you still want the timing information I would go for waveform. Then slipt the Y data out and do some kind of liner fit on all channels. Then take the channel that give you the steepest positive slop to see which one increased the most.
If you are only looking to which one that has the highest value. Then I would go for a MAX&Min function to determin which array (channel) that has the highest value (temperature) and then take out that row (Channel) from the wave form 2D array to only plot that one.
Does this make sense to you?
Best Regards
Jonas Mäki
Applications Engineering
National Instruments -
Getting data in a query on last date of all previous months
Dear Experts,
I need your help with a query.
I am trying to create a query which when run should pick the number of Open Sales Order on the last date of all the previous months from the start of company.
I could create the query for fetching the required data on last day of the previous month, say today is 25th June 2014, so my query only fetches data for May 31st 2014 but I need data for all previous month, May 31st 2014, April 30th 2014, March 31st 2014 & so on.
Please advise how to achieve this is SQL query.
Thanks & regards,
NitinHi,
Try this:
Select *
from(
SELECT T0.[DocNum] as #,t0.cardcode as C, t0.docdate
FROM ORDR T0
WHERE T0.[DocStatus] = 'o' and T0.[DocDate] = CONVERT(VARCHAR(10), DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,getdate())-1,0)),10) OR T0.[DocDate] = CONVERT(VARCHAR(10), DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,getdate())-2,0)),10) or T0.[DocDate] = CONVERT(VARCHAR(10), DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,getdate())-3,0)),10) or T0.[DocDate] = CONVERT(VARCHAR(10), DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,getdate())-4,0)),10) or T0.[DocDate] = CONVERT(VARCHAR(10), DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,getdate())-5,0)),10) or T0.[DocDate] = CONVERT(VARCHAR(10), DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,getdate())-6,0)),10) or T0.[DocDate] = CONVERT(VARCHAR(10), DATEADD(s,-1,DATEADD(mm, DATEDIFF(m,0,getdate())-7,0)),10)
group by t0.cardcode,docdate,T0.[DocNum]) S
pivot
(count(#) for c in([cvt01],[cvt02],[cvt03],[cvt04],[cvt05],[cvt06],[cvt07],[cvt08],[cvt12])) P
Note: Replace Cvt01,02...with your customer code.
Thanks & Regards,
Nagarajan
Maybe you are looking for
-
How to create multi axis graph with 2 on change of fields and 2 values
Hi all, i am working for a Semi conductor company and I have been madated to evaluate Crystal report 2008 in order to include it in our legacy software. So I have tested the soft and it seems to fit to our need. But I have a question... Here is a sce
-
"Connect to iTunes to use push notifications" That's the popup I'm getting.
-
I use a 'Geocaching" website, and am no longer able to see maps on the webpage
I go to 'Geocaching .com' and when I log on with my user name and look at a cache via 'Hide and Seek a Geocache', I get a page which shows me the cache details. This page should show me a map of the cache location, but the map is always blank now.
-
Hello excuse I have forgeoten that I was on an english forum ( because I am from france) I would like to know if I can use dreamweaver 8 to modify my web site written into xml I used to create in html so I could work into creative mode or in incoding
-
I had a Creative Vision:M 30GB for 2 years which I loved but the hard dri've gave out. I am considering the Vision 32GB but I have a question before I buy it. Does it have the ability to do A/V out? I loved doing that with my Vision:M. The videos loo