I'm looking to trigger data acquisition with a 9188 chassis, but the device I want to use to send the trigger pulse (servo drive) operates at 24V. Will this damage the chassis? Should I step the voltage down to TTL level?
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Will 24V on a PFI line damage a 9188 chassis?
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Controlling solid state switches
Hello,
I appreciate your help in advance.
I'm designing an a protection system for small electrical network.I'm trying to open and close solid state switches based on voltage and current measurements.
I will collect my measurements with 9205, my questions are:
1- Which one do u recommend for solid state switching 9375 with digital output or 9485 with external DC supply, given that the switch that i'm using accepts control signal from 4-32 VDC and maximum current is 25mA.
2- It is written in Ni 9375 manual that the digital output is based on the supply voltage, please clarify and what's the relation and how to select the supply voltage?.
3- If i intalled 9205 and 9485 or 9375 on chassis 9174 (4 slots) will it work properly without problems?
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Generating 40Mbit/s with pxie 6544
Hi,
I would like to know how to generate 40MBit/s continuously data through one channel with PXIe6544.
I've seen some continuous generation examples, but mostly are just generating some bits (which buffer may hold) and then repeat the generation all the time.
What if I have different data in my 40MBit and I may not split them into smaller pieces (then repeat generation) because the data are not repeatable until 40Mbit.
I cant update my data generation on the fly, its too slow for my HSDIO board to fill the buffer and generate signal. What is the alternative?
regards,
yan.
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Digital Trigger Vs Software Trigger.
I'm running an MCC USB-FS1608 DAQ to measure multiple analog voltage channels. I also have a digital in TTL coming from an MTS 407 frequency controller. Inside my VI, I read a rising TTL signal from the MTS, send a signal to switch on the digital out, then I start my data acquisition. At 1 Hz, would it be better to control my digital out, (which sends a run command to the MTS which then actuates a hydraulic piston) with a hardware trigger?
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Rs 422 interface dameged test
Hi guys I'm currently working with a Binder Oven and at the moment I believe the oven's Rs422 interface is dameged but I need to find a valid way to test it.
To communicate to this oven I am using a Startech 1 port Rs232/422/485 Over IP Adapter.
The interface to the oven is Rs422, although the protocol used to communicate is Modbus.
Researching Rs422 I found that is a differential bus having 4 lines to communicate.
Rx+
Rx-
Tx+
Tx-
Now when I measure the voltage levels on the Star tech device I find that the Tx+ and Rx+ lines are +5V and the TX-/Rx- lines are 200mV.
When I try measure the interface on the Binder Oven I find that there is no voltage at all on these lines? (Measuring using an oscilliscope and multi meter)
My question is is there a valid way to test an RS-422 interface that is on a machine and not on a PC's communications port?
I have searched all over online but I still havent found a valid test.
Thank You.
T2DJ.
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Bertec force plates
Hello,
Does anyone know how to connect Bertec force plates to Labview? I would like Labview to read the data from the force plates, then when the forces on the force plate reache a particular threshold, I would like to to activate an image on the front panel. I don't know if I need a DAQ card, or if I can use a Constructor node. I tried a constructor node, but I was unsuccessful.
Thank you
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Issue with moving from Traditional DAQ to DAQmx using NI-6534
I am trying to move the following code from Traditional DAQ to DAQmx:
This code is used to send data to program a FPGA using a PCI NI-6534 DIO. This code works like a charm, but when I try to write the equivalent code using DAQmx (in LV 8.6 as well) it doesn't work. I don't get any errors, but the FPGA does not program.
The general procedure is as follows:
Set all lines on Port 0 to Output
Configure transfer mode to Active Low
Write the data to the buffer
Send the data using the 10MHz internal clock of the 6534 (6533 is no longer used but the code was never updated)
Wait until the output is done
Clear the task
In DAQmx I have it set up as such:
Any ideas on what has changed in DAQmx or what I'm doing wrong?
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NI 9402 generate two trigger signal from 2 different lines with 10ms apart from each other
Hello,
I am trying to use NI 9402 to generate two trigger signal from 2 different lines. The time interval between these two trigger pulses is critical (should be accurate at 10 or 25ms from each other)
I think software timer is not accurate enough for my purpose
Is there a way to make this possible? Please help!
Thank you,
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NI USB-6009 Analoges Ausgangsignal erzeugen
Hallo,
ich habe mir ein NI USB-6009 Datenerfassungsmodul angeschafft und die Installation hat soweit funktioniert.
Im MAX hab ich schon alles Ausprobiert und es hat auch alles so weit funktioniert.
Nun wollte ich das Geräte mit ein paar DAQmx Beispielen von NI testen, besonders die Analoge Signalerzeugung.
Zuerst habe ich das Beispiel "Voltage - On Demand Output" getestet. hat alles super Funktioniert. Konnte die Spannung perfekt einstellen.
Dann wollte ich mir ein Sinussignal mit Hilfe des Beispiels "Voltage - Finite Output" erzeugen. Hier erhielt ich leider eine Fehlermeldung, dass was mit dem Takt nicht stimmt! (siehe Bild)
Kann mir bitte jemand weiter helfen und mir sagen, was dieser Fehler bedeutet und wie ich ihn beheben kann?
Vielen Dank schon mal im Voraus
Mfg Firedevil87
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NI USB-6210 Noise issue (Voltage analog input)
I recently purchased the NI-USB-6210 to replace my old voltmeter, Keithley 197A. After installation and initial testings, I found that the baseline noise was significant increased.
For the same setting, my old Keithley 197A meter measured 5.0000+/-0.0001 V. However, the new NI-USB-6210 measured 5.00+/-0.01V. The noise is 100 times higher.
At a lower voltage, it's 0.500+/-0.002V VS 0.5+/-0.4V. The noise is too high. According to the spec of 6210, it measures 10 V in 16 bit, and this translates to 0.1 mV. So I suspect the card may be defective.
Does anyone have the same issue? Would this be defective or could it be some settings to increase the resolution?
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How do I output a continuous 5V line from my cDAQ9174?
Hi, I'm looking at having a constant 5 V line and a constant ground line out of my CDAQ 9174. I'm new to LabVIEW and didn't understand the example LabVIEW 2012 had (and it didn't run when I tried).
This must be more complicated than have an I/O feed into a DAQmx Digital Output, that then feeds into either a DAQmx Digital Write or clock then DAQmx Digital Write.
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USB-6501 voltage generation
Hi all,
I'm very new to using LabView and NI devices, so pardon me if my question seems dumb.
I have a NI USB-6501 DAQ that I would like to use to connect to a device that will open or close a lid when triggered.
My question is: Is it possible to programmatically trigger the voltage output of the USB-6501?
I'm using LabView for this and I'm running on Windows 7. I couldn't find basics examples on LabView that were related to the voltage output for the USB-6501.
Any help would be really appreciated, thanks in advance
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problems communicating using 845x .dll in vb.net
I am trying to use the .dll supplied with the 8451 to communicate via SPI, and I have most things (seemingly) working. When I try to send a message, however, I get an error (-301710 - invalid configuration reference). Some of the documentation for the dll is... lacking, but I tried passing the configuration handle by reference and value, both giving the same error.
My code flow is as follows:
1. Find device with ni845xFindDevice
2. Open device with ni845xOpen
3. Open device configuration with ni845xSpiConfigurationOpen
4. Set all configuration parameters with their functions
5. attempt to write data with ni845xSpiWriteRead
It fails at step 5. In addition to changing how the variables are called, I switched steps 2 and 3 to no avail as well. I also pass the configuration handle as a reference to a subfunction that performs all of parts 3 and 4. I am storing the device handles as ULong (which I grabbed from the .h file that was included) and this works for the other functions that require handles.
Does anyone have advice on what to try next?
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Generating arbitrary digital waveforms
Hello,
I'm new to the world of hardware-timed digital signals, so I'm unsure of how to proceed. I have a cDAQ-9174 and a NI 9474, which I'd like to use to produce two periodic, synchronized digital signals:
What's a good way to accomplish this? I found the DAQmx "Generate Signals" -> "Digital Output" task, but that seems to only generate uniform pulse trains, not the arbitrary waveform I'm looking for.
Thanks in advance.
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rs232
When I run basic write and read.vi , I use a virtual com port for my PC doesn't have it. The program can run without any error,but the string indicator can't show what I write. I want to know why ,thanks !
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Using NI USB-4431 digital input as tachometer
Dear Friends
I would like to know whether it is possible to connect a lazar tachometer to the NI USB-4431 digital input in order to measure the rotation speed of a shaft.
Many thanks for your cooperation.
Best Regards
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DAQ Interfacing problem
I have to generate a 12 bit combination Digital output . I made a vi accordingly but on fixing the prob the out is showing, but at DAQ output the response is not the same while checking with multimeter. I am using NI USB 6009
Please help me to solve this
Thanks in advance
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generate a 12 bit digital output at DAQ output pin
Hi
I have only a little knowledge in Labview
I want to generate a 12 bit digital output at DAQ output pin , from a decimal number. I am using NI USB 6009
Thanks in advance
regards DK
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What hardware should I use for TTL synchronization?
I am searching for a hardware recommendation. Here's what the hardware should do: notify a PC program to run a subroutine upon detection of a TTL pulse (digital input change).
So I need one 1-bit digital input, and the device should communicate with a computer via USB. The TTL pulse voltage is about 4.7 V. Since the synchronization must be fairly precise, the delay should be on the order of 1 ms or less. Therefore the hardware should have a sampling rate of at least 1 – 10 kS/s.
I purchased the USB-6501 not realizing that it doesn't have any triggering or interrupt functionality, and now I don't think it will work for my application. I could constantly poll one of its inputs with my software to check for a change in value, but that would be relatively slow and hog my CPU. I would prefer that the device triggers or provides some kind of interrupt to my software application. I am considering using some NI software, but right now I'm using the session-based interface of the Data Acquisition Toolbox in the latest version of Matlab (R2013a, 64-bit) on 64-bit Windows 7.
I think either the USB-6008, USB-6009, or USB-6525 might be a good option, but I'm not sure. I don't fully understand the difference between the triggering/interrupt capabilities of the USB-6008/9 and the USB-6525. Any advice?
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NI PCIe-6351 Count Edges Channel error on fast TTL - Multiple Sample Clock pulses were detected
Hello,
I am trying to use a PCIe-6351 to record the arrival times of a fast TTL pulse stream (generated by an Excilitas/Elmer Perkin APD). The TTL pulses are 2.5 volt amplitude, 20 ns duration, with a gauranteed dead time of 50 ns between pulses. I am trying to use the the Count Edges function, with the 100MhzTimebase as the input terminal and the input to counter 0 (PFI8) as the sample clock. After a few seconds of acquiring data at 100 Mhz, the application throws the following error (-201314):
"Multiple Sample Clock pulses were detected within one period of the input signal"
I had thought that because there is 50 ns dead time between pulses, multiple pulses would never arrive within a single clock cycle of the 100 Mhz timebase. Is there any way this might not be the case? Alternatively, is it possible that the counter is triggering on some jitter around the edges of the pulses? If so, is there any way to filter such high frequencies without losing the 20 ns pulses?
I have read through the forums for similar problems with photon detectors, but have not been able to resolve this issue. Thank you for the help.
Matthew Bakalar
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