How to measure a current signal with NI 6211?
How to measure a current signal with NI 6211?
Hi Clecio,
This is a charge accelerometer. It is different from the IEPE accelerometers that outputs a voltage signal.
You need a charge amplifier. Then according to the charge amplifier output we can select an appropriate module to measure the signal.
It is not possible to measure charge accelerometers with NI 9234 directly.
Best Regards,
Rodrigo Schneiater
Application Engineering
National Instruments Brazil
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I tried to read the first signal and everythings was OK, then I tried to read the second and everything was Ok, but when I tried to read them togheter the values were modified from original values, even measuring them with an external voltimeter.
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Thanks
LorenzoHi lcaggio,
You're BNC-2210 is designed to work in differential mode with your DAQ board. It sounds like this is how you have things configured though. Here are my main suggestions for resolving this.
1) Make sure that the channel switch is set to "FS".
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Now, by default, the NI-DAQ driver will sample channels as quickly as it can between channels. Since your channels are floating, it is possible that there is channel cross-talk between your two channels and that is why it l
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4) The following Knowledge Base describes and links to documents that mention the importance of the interchannel delay.
What Are the Minimum and Maximum Values for the Interchannel Delay Setting on my DAQ Board?
http://digital.ni.com/public.nsf/websearch/9AE87416C8792FC286256D190058C7D3?OpenDocument
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I need to measure high currents accurately. I have only a FPGA board and TBX 68 terminal block. Do I need any other NI hardware?
The answer will depend on your specific situation, such as the voltage levels you are working with, the source of the current, the influence some additional components such as a shunt resistor may have, etc. Can you provide more details about the application, the source of the current, the voltage levels, how quickly the current will change, the stimulus for a current change, etc.
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This is probably the simplest approach. If this setup is not feasible (e.g. the voltage in not within the 7831R input range) then you will need some additional signal conditioning. There are some off-the-shelf components for measuring larger currents that would translate the current into a voltage that you can measure with the FPGA board. Look at the following component as a place to get started.
A closed loop current sensor like the following may work. It runs off a 5 V supply, and is relatively easy to wire up:
http://rocky.digikey.com/scripts/ProductInfo.dll?Site=US&V=102&M=SCD20PUN
Christian L
NI Consulting Services
Christian Loew, CLA
Principal Systems Engineer, National Instruments
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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
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end;'
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Hi,
I was wondering how to convert a complex baseband signal with bandwidth 20MHz to an RF signal with center frequency 2.4GHz and the same bandwidth 20MHz in simulation. I tried
1. Multiplying the complex double type baseband signal (1-D array) by exp( j * 2 * pi * 2.4E+9 * T ) where T is the symbol period of baseband signal.
2. Usage of MT upconvert baseband but doesnt keep the BW constant
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http://support.apple.com/kb/SP28
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Thanks,
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~~~~~~~~~~~~~~~~~~~~~~~~~~
"It’s the questions that drive us.”
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Hi!
We're using SCXI-1128 switches with 1331 terminal blocks. The switches should communicate with the PCI DMM 4060 via the SH9MD cables.
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I have one ADF page with one table and one "Find" button.
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Thanks.Hello Kumar,
I have some comments on your case.
>
I have created one new attribute with VARCHAR2(1) in the VO
>
1- You should create this attribute in the Entity object and then add it to the view object.
2- Do you need that only one radio button is set at a time for all rows ? If yes then you need to handle the case when the user set more than one row and clear the value of the attribute for all other rows.
>
How can i get all the values of current row in backing bean method(method binding of Find method)?
can u plz provide me the code for that?
>
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Hi,
currently there are two different audio drivers on my solaris 10,
pkginfo | grep 810
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thanks !In another thread we've already found out that the pci vendor/
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Hi Everyone , I need your help .
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