USB-6259 to capture the current waveforms

Hi all,
I am pretty new to LabView and data aquisition. Sorry to bother you all. I have a question:
"Can I use the USB-6259 DAQ device to capture the current waveform of electrical appliances e.g. electric kettle using current probes????? If yes, could you be very kind to guide me in this regard???"
Thanking in anticipation.
Best regards,
Haroon

Yes, you can do that. You need to do the following:
1. Put a shunt resistor (1ohm, high precision, high wattage) in series with your application.
2. Use one of the Analog input from your DAQ to measure the voltage drop across the shunt, and this will be your current waveform, since the resistor has 1 ohm.
Things to watch out for:
1. Power rating on shunt: make sure your shunt can handle the power.
2. Noise: you may need some filtering circuitry to get rid of the signal noise. If you are comforable with digital filtering, you can use some of the filtering function in LabVIEW.
3. Level at AI: maybe very low, since there are little drop across the shunt. If you don't mind a larger voltage drop, you can increase the value of the shunt to increase the level; if you just want to look at the pulse shape. Or, you can put an amplifying circuit for a little boost before you feel the signal to AI.
Yik
Kudos and Accepted as Solution are welcome!

Similar Messages

How to capture the current info in the top-of-page event in Reuse block dis

How to capture the current info in the top-of-page event in Reuse block dis

Hi Geetha,
     If you don't have any information to pass the Heading Block, then why you are using this event ?
     please comment/ remove that TOP_OF_PAGE code. and use subtotal code in field catalog block.
      you can use below code for subtotal.
      FORM field_catalog .
                gs_fcat-do_sum = &2.
          fcat : 'WRBTR' '15' 'X' ' ' ' ' 'WRBTR' 'Amount',
       ENDFORM.
       Regards,
       Kunjan

Using a bean to capture the currently authenticated user information

Hi,
i have an ADF web based application . The authentication and authorization is managed by OID(LDAP) . I want to put user level access in the application. I have made a custom method in the application module, that handles the authorization at user level. But i do not know how to capture the info of currently logged in user. I'am aware i can do this using a bean. Can someone tell me how

It'd be better to post this to the JDeveloper forum where ADF is covered.
cheers
-steve-

Capturing the current ALV grid contents. How?

Hi forum,
After lots of searching, I still can't find out how I can get the current contents of the ALV grid. I need this for an editable ALV grid to keep track of the data changes.
By the way, I am using the traditional ALV, not OO ALV.
Let me share the steps I already did but still failed.
1
I used the FM GET_GLOBALS_FROM_SLVC_FULLSCR to have access to the CL_GUI_ALV_GRID object. I tried using some of the methods inside that class, all to no avail.
Some methods I tried were set_selected_columns and set_selected_rows and then call the method get_selected_cells. Basically, the idea is to simulate highlighting of cells, and select them using get_selected_cells. But the problem is that get_selected_cells is not returning the value (although it correctly returns the row and column that I set -- but not the value in that cell coordinates).
2
I also saw the protected method get_changed_data -- but the problem is that it is protected, so I created a subclass of CL_GUI_ALV_GRID to ZCL_GUI_ALV_GRID and copied the private attributes and methods that get_changed_data depends on. I was able to do this but GET_GLOBALS_FROM_SLVC_FULLSCR strictly returns CL_GUI_ALV_GRID. The upcast from CL_GUI_ALV_GRID to ZCL_GUI_ALV_GRID fails. So I still can't use/test get_changed_data.
3
I also saw some code regarding events. Here's a sample but this doesn't work:
    REFRESH lt_events.
    lwa_event-name = 'DATA_CHECK'. "Event name
    lwa_event-form = 'HANDLE_DATA_CHANGED'.
    APPEND lwa_event TO lt_events.
    CALL FUNCTION 'REUSE_ALV_GRID_DISPLAY_LVC'
        EXPORTING
            it_fieldcat_lvc         = it_fieldcat
            is_layout_lvc           = ls_layout
            it_events               = lt_events
FORM handle_data_changed using ref_data_changed
                          type ref to cl_alv_changed_data_protocol.
    BREAK-POINT.
ENDFORM.
I would really appreciate it (and I know a lot of other ABAPers will, too) if you could point me to how I can get the ALV grid contents. Thanks.
Kyle

Hi Keshav,
sure I will check those tomorrow when I get back to work.
All,
Here's the code if it helps:
*& Report Z_ALV_EDITABLE
REPORT Z_ALV_EDITABLE.
TYPE-POOLS:
    slis
DATA:
    BEGIN OF i_out OCCURS 0,
        operand1 TYPE i,
        operand2 TYPE i,
        operator TYPE c,
        result   TYPE i,
    END OF i_out
START-OF-SELECTION.
    PERFORM prepareData.
    PERFORM refreshResults.
    PERFORM createALV_LVC.
FORM prepareData.
    REFRESH i_out.
    DO 10 TIMES.
        i_out-operand1 = 1.
        i_out-operand2 = 2.
        i_out-operator = '+'.
        APPEND i_out.
    ENDDO.
ENDFORM.
FORM refreshResults.
    LOOP AT i_out.
        CASE i_out-operator.
            WHEN '+'.
                i_out-result = i_out-operand1 + i_out-operand2.
            WHEN '-'.
                i_out-result = i_out-operand1 - i_out-operand2.
            WHEN '*'.
                i_out-result = i_out-operand1 * i_out-operand2.
            WHEN '/'.
                IF i_out-operand2 NE 0.
                    i_out-result = i_out-operand1 - i_out-operand2.
                ENDIF.
            WHEN OTHERS.
                i_out-result = ''.
        ENDCASE.
        MODIFY i_out.
    ENDLOOP.
ENDFORM.
FORM createALV_LVC.
    DATA:
        it_fieldcat TYPE lvc_t_fcat,
        ls_layout   TYPE lvc_s_layo,
        lt_events   TYPE slis_t_event,
        lwa_event   TYPE slis_alv_event
    " Field Catalog
    PERFORM createFieldcat CHANGING it_fieldcat.
    " Sorting
    PERFORM createSort.
    " Layout
    ls_layout-cwidth_opt = 'X'.
    " Events
    REFRESH lt_events.
    lwa_event-name = 'DATA_CHECK'. "Event name
    lwa_event-form = 'HANDLE_DATA_CHANGED'.
    APPEND lwa_event TO lt_events.
    CALL FUNCTION 'REUSE_ALV_GRID_DISPLAY_LVC'
        EXPORTING
            it_fieldcat_lvc         = it_fieldcat
            is_layout_lvc           = ls_layout
*            it_sort                 =
            it_events               = lt_events
            i_callback_program      = 'Z_ALV_EDITABLE'
            i_callback_user_command = 'USER_COMMAND'
            i_callback_pf_status_set = 'PF_STATUS_SET'
            i_save                  = 'X'
        TABLES
            t_outtab                = i_out
        EXCEPTIONS
            program_error           = 1
            OTHERS                  = 2.
ENDFORM.
FORM createFieldcat CHANGING it_fieldcat TYPE lvc_t_fcat.
    DATA:
        wa_fcat LIKE LINE OF it_fieldcat
    REFRESH it_fieldcat.
    DEFINE m_append_fieldcat.
        CLEAR wa_fcat.
        wa_fcat-edit      = &1.
        wa_fcat-fieldname = &2.
        wa_fcat-scrtext_m = &3.
        APPEND wa_fcat TO it_fieldcat.
    END-OF-DEFINITION.
    m_append_fieldcat '' 'OPERAND1' 'Operand 1'.
    m_append_fieldcat '' 'OPERAND2' 'Operand 2'.
    m_append_fieldcat 'X' 'OPERATOR' 'Operator'.
    m_append_fieldcat '' 'RESULT'   'Result'.
ENDFORM.
FORM createSort.
ENDFORM.
FORM PF_STATUS_SET USING    P_EXTAB TYPE SLIS_T_EXTAB.
    SET PF-STATUS 'Z_ALV_STATUS' EXCLUDING P_EXTAB.
ENDFORM.                    "PF_STATUS_SET
FORM user_command
    USING
        r_ucomm TYPE sy-ucomm
        ls_selfield TYPE slis_selfield.
    CASE r_ucomm.
        WHEN 'REFRESH'.
            " CHECK i_out HERE IF IT CHANGED ALONG WITH THE EDITS
            BREAK-POINT.
*            PERFORM refreshALV.
    ENDCASE.
ENDFORM.
FORM handle_data_changed using ref_data_changed
                          type ref to cl_alv_changed_data_protocol.
    BREAK-POINT.
ENDFORM.

Error while trying to retrevie the Current Portal Language

Dear All,
In my present application,I need to pass the language as a parameter to the backend.As my application needs to support different languages.In this regard I need to capture the current user language and if the user language is not mentioned then it should take the Browser language and even if that is not present it should take the server language.
I am Using XLF Files in Webdynpro for the language change in Appilcation Screen and it is working properly.
The present code which I am using to get the language is:
CODE:
IWDClientUser user = WDClientUser.getLoggedInClientUser();
IUser iuser = user.getSAPUser();
String userid = iuser.getDisplayName();
wdComponentAPI.getMessageManager().reportSuccess("userid"+userid);
iuser.getLocale();
But when i am trying to print it.I am getting an Null value.Can anybody please let me know if i am going the right way and help me in getting the language of the user.
Thanks in Advance
Thanks and Regards,
Nishita Salver

Hi,
Try this code
try {
IUser user = WDClientUser.getCurrentUser().getSAPUser();
wdComponentAPI.getMessageManager().reportSuccess( user.getUniqueName() + " " + user.getLocale().getDisplayLanguage());
} catch (WDUMException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
Regards
Vinod V

Q: How to retrieve the current URL with PL/SQL

I've got a pair of dynamic page portlets on a page. The first is simply an input text box and a submit button, the second is an inventory 'report' based on what is entered in the text box. When a value is entered and the button pressed, there is javascript behind the button that takes the current URL, adds '&ITEM=XXXXXXXX' (removing it first if this is not the first invocation of the page), and redirects to the new page.
The second portlet uses the &ITEM parm to list a bill of materials for the item. If one of the items possesses a sub-assembly, I want to display the item# in an <a href= manner to make it so the user can simply click on the link to see the BOM of the subassembly.
To do this, I believe I need to capture the current url and modify it as required to pass the new &ITEM value. I'm having a lot of trouble trying to figure out how to get the current page url. Any help would be greatly appreciated!
Geoff

Hello
I have a similar problem I have developed a pl/sql portlet and put it into a page, this portlets display a dynamic page. This dynamic page have a search functionality, what I am trying to do is that when I click the search button on the dynamic page it recall the whole page and pass the paremeter that the user wrote on the search box, then the portlet that contains the dynamic page recieve the parameter and recall the dynamic page with the parameter that was received. The problem that I have is that the portlet receive the parameter but when I pass the parameter to the dynamic page it doesn't get it. This is the way the I am calling the dynamic page inside my portlet into the show procedure:
EXECUTE IMMEDIATE
'begin
APP_NAME.PG_DYN_DIR_ALFABETICO.show (
p_arg_names => PORTAL30.wwv_standard_util.string_to_table2(''url_page'',''search_param''),
p_arg_values => PORTAL30.wwv_standard_util.string_to_table2(:1,:2));
end;'
using url_pg,p_text1;
The dynamic page receive the first parameter(url_page) but not the second one(p_text1), I have checked that the p_text1 has a value on my portlet before I send it to the dynamic page so I really don't understand why my dynamic page doesn't work.
Please HELP ME. I am desperate
Ana Lasprilla

How can I make the current date/time be sent when emailing as XML?

I'm creating a form for a customer to use for submitting print jobs. This customer will be emailing the XML form data, which will in turn be converted into a production order. I'd like to make the PDF form capture my customer's system time, so that I know when they filled out the form. I COULD just leave that up up the customer and use required current date and time fields, but that provides the ability for the customer to falsify that information.
Is there any good way to capture the current date/time in the XML data, so that the customer doesn't need to nor has the ability to?
Any suggestions would be great!

You can use the following methods getHours(),getMinutes(), and getSeconds() from the date object to obtain the values for hour,minute,and second.
Click here to see an example:
http://66.34.186.88/LiveCycleSamples/.3bbc2f4b.pdf

Capacitor & inductor current waveforms not showing correctly

Hello,
After a fair amount of time playing around, I cannot seem to get the current waveforms of a purely capacitive / inductive circuit to show correctly on the oscilliscope.
since I through inductor =( ∫v dt) / L
I get extremely high current values on the oscilliscope (in the region of kA) adn for a purely capacitive circuit - in the region of pA.
ie, a square wave DC source, 10V to -5V, 1ms @ 10V and 2ms @ -5V, period of 3ms - connected to a 1mH inductor.
(∫10 dt)/L = (10 x .001) / .001 = 10A - so at 1ms, the current will rise to 10A ( in a linear fashion)
[(∫10 dt) / L] from 0 to 1ms + [(∫-5 dt) / L] from 1ms to 3ms = 0 = current will drop to 0A in a linear fashion from 1ms to 3ms.
THIS does not show on the osciiscope!
By adding an instantaneous current probe onto the circuit - this will roughly show the correct value - but obviously will not show an accurate waveform.
Any help would be extremely appreciated.
Many thanks.

Thanks for your reply,
I'm using 12.0.1 power pro edition
I literally just opened up the file to check it and to post it here, and it works?!
Rather confusing as it was most definately not working when I started this thread.
Maybe the program needed and clean startup or something.... but the current values were all over the place.
When I analysed the circuit by hand, I would get values for current and voltages but when simulated they were in the range of 500KA etc with a simple capacitor circuit with a 10V sawtooth supply.
Thanks anyway.
SS

16 channels of data at 30kHz on the NI USB-6259 - is it possible?

Hello -- I would like to use the NI USB-6259 for electrophysiology. My application requires 16 channels of analog input digitized at 30kHz. This should be possible, as the listed aggregate digitization rate is 1MS/s. I've however run into several problems, all of which I believe may deal with how memory is handled in LabView (or maybe I'm just programming it wrong).
First off, if I pull in continuous voltage input using the DAQ assistant (DAQA) from anywhere from 5k to 30k samples at a time -- without any visualization -- things run alright. I record the data in binary format (TDMS) using the "Write to Measurement File (WTMF)" routine. However, I notice that the RAM used by LabView creeps up at a steady pace, roughly a megabyte every several seconds. This makes long-term recording unfeasible. Is there any way to avoid this? Basically I just have the DAQA and WTMF in a while loop that was automatically created when I set the acquisition mode to continuous.
Secondly, I would like to be able to visualize my data as I record it. If I set up 16 graphs -- one for each signal -- I need to raise the "Samples to Read" (STR) to 30k to ensure that the "Attempted to read samples that are no longer available" error [-200279]. This is annoying, as it makes the display look jerky, but is probably livable.
Now if I choose to display data in 16 charts rather than graphs (charts, as defined in LabView, display a bit of cumulative data along with the real-time signal), the amount of RAM used by LabView increases by several megabytes a second, regardless of whether or not I'm saving the data. After a short time, I get an "out of memory error".
Ideally I would like to be able to display 16 channels of 30kHz analog voltage data and save the data. As you see I'm having some level of trouble doing either of these things. Bare minimum requirements for my application would be to pull in the data with an STR of 30k, visualize the data in graphs, and save the data. Should this be possible in LabView 8.6 or 2009 (I use 8.6, but have tried these steps on the trial version of 2009 as well)? Even better, I would like to use an STR closer to 5k, and display the data in charts as it's saved. Should this be possible?
I'm using a reasonably powerful machine -- 32-bit Windows 7 with 3.24 gigs RAM, 2.4 GHz quad-core, etc.
Thanks

Hello!
I will admit right now that I can't stand any of the "assistants" and never use them. I don't like to have any part of my code invisible from me. Therefore, looking at your code gave me a headache. :-)
So, what I did is rewrite your code using the DAQ functions (basically what you'd see if you selected "Open Front Panel" on the DAQ assistant icon). You can go in and put the DAQ assistant back in if you so desire. This is just to give you an idea of the approach you should take. I'm grabbing 15000 points per loop iteration, just because I happen to like 500msec loop rates. You can tailor this number to your needs.
I have two parallel loops -- one collects the data and the other displays it on the front panel and writes it to a file. (I used the "Write waveform to file" function -- you can put your assistant back in there instead if you like.) The data is passed from the DAQ loop to the display loop using a queue. I use the "index array" function to select out the individual channels of data for display. I show 3 channels here, but you can easily expand that to accommodate all 16. You can also add your filtering, etc.
I am using a notifier to stop the two loops with a single button, or in case of an error. If "stop" is pressed, or an error occurs in the DAQ loop, a "T" value is sent to the notifier in the display loop (and that "T" value is used to stop the DAQ loop as well). That will cause the display loop to receive a "T" value, which will cause it to stop.
I don't have a 6259 on hand, so I simulated one in MAX. I didn't have a problem with the processor running at 100% -- on my clunky old laptop here, the processor typically showed ~40-50% usage.
I've added comments to the code to help you understand what I'm doing here. I hope this helps!
d
P.S. I have a question...how are you currently stopping your loop? You have "continuous samples" selected, and no stop button.
Message Edited by DianeS on 12-30-2009 07:28 PM
Attachments:
16 channel waveform display and write.vi ‏31 KB

SignalExpress and the usb-6259

We are trying to use SignalExpress and the USB-6259 to generate digital outputs without success. Do all the digital I/O lines on this module require an external sample clock to work correctly. Any information would be appreciated

Hello Greenies
Thank you for your posts, as I have said on your other message, I hope it is ok for me to contact you on just the one page as it saves repeating ourselves. I would also like to mention that in future it is better to post on one board so that other users can search discussions with more ease.
As I understand you have queries regarding the digital I/O of the USB 6259, I firstly recommend looking in the manual for your device to see if this is already documented.
"Each DIO and PFI signal is protected against overvoltage, undervoltage, and overcurrent conditions as well as ESD events. However, you should avoid these fault conditions by following these guidelines:
• If you configure a PFI or DIO line as an output, do not connect it to any external signal source, ground, or power supply.
• If you configure a PFI or DIO line as an output, understand the current requirements of the load connected to these signals. Do not exceed the specified current output limits of the DAQ device. NI has several signal conditioning solutions for digital applications requiring high current drive.
• If you configure a PFI or DIO line as an input, do not drive the line with voltages outside of its normal operating range. The PFI or DIO lines have a smaller operating range than the AI signals.
• Treat the DAQ device as you would treat any static sensitive device. Always properly ground yourself and the equipment when handling the DAQ device or connecting to it."
This information was taken from chapter 6 of the manual, there is also information about connecting signals for DIO on page 10 of chapter 6.
Specifications
Manual
Here are some articles which discuss DIO functionality, these may also help you with your development.
DIO benchmarks
DIO
Please let me know if your questions are answered in these documents, if you still have outstanding queries, please reply so I can continue to offer you support.
Regards
Stephanie L
Applications Engineer
National Instruments UK and Ireland

Is there a compatibility issue with the Current USB 3 external Hard drives and MacBook Pro 2011 (USB 2)?

I am currently having bad hangs with my 13" MacBook Pro (2011) which I book 2012 ad a New external Harddrive (WD My Passport Edge) which was given to me as a gift.
Friends of mine told me there is a compatibility issue between the USB 3 cord and the USB outlet of my MacBook Pro.
Although this shouldnt be the case as the box of the Hard drive I got said it was compatible.
I even downloaded the WD Drive Utilities and sometimes whenthe Harddrive is plugged in the Utilities doean't Open but just bleeps in the Applications Dock.
Before I used the Harddrive I read a lot from the WD Manual and went to their site and downloaded a firmware update so I really don't know what the problem is.
What I am afraid of is that I may lose some files if I place them in the external Harddrive.
Can anyone help me with this or should I be asking for a replacement harddrive?
This is my first experience with an external hard drive as I never used one before.
Thank you very much.

To be honest, I've had back luck with Western Digital drives and I avoid them at all costs. If I were you, I would return the WD drive and look at externals from OWC or MacMall (LaCie, even G-Tech).
That's just my personal opinion, mind you...
Clinton

Is there a way to live capture in FCP X? I use a SONY NX 70U. It only has usb 2, HDMI and the weirdo sony protocol.

Is there a way to live capture in FCP X? I use a SONY NX 70U. It only has usb 2, HDMI and the weirdo sony protocol. If not with THIS camera as I have described, is it possible with any other cameras?
Thanks.

Is there a way to live capture in FCP X? I use a SONY NX 70U. It only has usb 2, HDMI and the weirdo sony protocol. If not with THIS camera as I have described, is it possible with any other cameras?
Thanks.

Local USB "There's no media in the current folder"

Hi Forum, I have a no media in current folder error with my WDTV Plus. I searched the forum and googled for hours but everyone seems to have this problem with network streaming or the suggestions don't work for me. My media is on a Seagate 3TB USB Drive which is connected directly to the WDTV, no ethernet cable in use, everything local.This setup worked for three years now. Two months ago, some subfolders began to have the "no media" error, but most of the files worked. Now I get this error in the root and I am not able to play a single file.The USB drive is formatted with ntfs. What I noticed:- I also get an error when I choose USB Storage in the menu (right before it would show the folder structure where now the no media error appears). It says "Unable to create media library. check your storage setting".- the .wd-tv folder in the root of the disk always has the last changed date 01.01.2000, all other files have timestamps from the last 3 years.- When I go to file management on the wdtv I can see all my files and folders. I can even delete and copy them around. What I've done so far:- Updated to the newest firmware, nothing changed.- Plugged my USB disk to my laptop and checked it for errors. This took 48 hours and there where 0.0% errors, destroyed blocks or something.- Played around with the folder structure, copied files to other folders... I also read that there has to be at least one media file in every subfolder, otherwise wdtv would come up with the no media error. So I did this -> nothing changed.- Deleted the .wd-tv folder on the disk many times. Played around with the "create media library" setting on the wdtv. It can create a media library (the .wd-tv folder), despite the error "unable to create media library".- Permissions on all folders and subfolders on the USB drive are full control for everyone.- When I plug in a 16GB usb flash drive with some video files on it everything works fine. could it be that there are some currupted files that wdtv can't read? If so, how could I detect them?Has anybody occured the same sort of problem? Thanks in advance,Sandro

Hi,
See if the following link helps.
http://community.wd.com/t5/WD-TV-Live-Live-Plus/quot-There-is-no-media-in-the-current-folder-quot-Oh-yes-there/m-p/291008#M25793

The current capture scratch drives are too full

I just downloaded this software on my Mac and I am captuing HD video from a Mini HDDV tape camera. I got a error message half way while captuing video
"the current capture scratch drives are too full. Please remove files from these drives or select a new capture scratch location."
How can I move forward with capturing video?

I just downloaded this software on my Mac
How so? Final Cut Express has never been downloadable and was discontinued over 18 months ago. Are you sure you didn't actually download Final Cut Pro X?
Also, it will help us to know exactly what model Mac you are using, what version of OS X, version of FCE and make/model camcorder you are using.

My IPhone stopped working right after I did the most current update, yesterday. The screen has a picture of the usb cord, pointing towards the ITunes logo. I cannot use the phone at all. I have tried turning it off and on.ITunes won't recognize device

Hi there,
Can someone please help. My IPhoneS stopped working right after I did the latest update which was yesterday. Now, the phone does not work at all. When turned on, the screen shows a picture of USB cable pointing to the ITunes logo. I have tried just about everything, and cannot get it working. It's like it is frozon. My ITunes does not recognize my device. Cannot dial out either. I desperately need to get it working. Can someone please help me.
Thanking you in advance for your help. :-)

The update did not do anything.
AT&T cannot and will not do anything, they do not provide support for iPhones, Apple does.
The issue is not with the iPhone or iOS if you've reset network settings and tried forgetting the Wi-Fi Network, it is specific to the network.
Check the settings on the router, try disabling the security settings first... that will clarify the issue is not with the device but rather the Network.

USB-6259 to capture the current waveforms

Similar Messages

Maybe you are looking for