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Different Signal synchronization NI Digital Pattern Editor LabView Code with two PXI 6570

June 5, 2018, 1:17 pm
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Hello Community,

 

I hope that is the right place for my question. 

I have a timing problem(delay) between two signals at different PXI6570 cards.

 

My Hardware Config:

    NI-PXIe-1082
    Slot4 - NI-PXIe 6674T
    Slot 2/3 und 5/5 NI-PXI 6570

 

My problem discription:

In case I let run the pattern "Timing_Debug.digipat" im "NI Digital Pattern
Editor", is the signal difference is lower than 1.5ns. (Timing_with_Pattern_Editor_TDR.png)


The other case is I use the same pattern in a TestStand sequence and *.vi and get a signal delay of about 10ns. (Timing_with_LabViewCode.png)

The Time-Domain Reflectometry (TDR) option and syncronisation is in both cases activated.

 

Could anyone tell my what is wrong in the *.vi?

 

I attatched the Project and Pattern.

 

Many thanks.
Regards,

Matthias

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PCI 6515 to drive 15VDC IGBTs of an inverter

June 7, 2018, 9:43 am
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Hello,

I'm using PCI 6515 digital outputs to drive a 15 VDC IGBTs of an inverter. I wasn't aware of the idea of sinking and sourcing Digital I/O, and PCI 6515 seems to have sinking digital outputs. According to this page: http://www.ni.com/white-paper/3291/en/ , I can't power the device (IGBTs) with a sinking output. However, taking a look at the user manual of the PCI 6515: http://www.ni.com/pdf/manuals/372172b.pdf, I found this example circuit: https://ibb.co/eDe0yT in which it seems that the device (load) is powered with the sinking output!! I'm confused whether I can use the PCI card for my goal or not.

I appreciate your help.

Thanks.

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Max. frequency of acquiring data in PCI 6515

June 7, 2018, 9:59 am
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Hello,

I'm using PCI 6515 digital inputs to acquire a 64K quadrature encoder pulses attached to a motor with maximum speed of 3000 RPM. The encoder has two options of resolutions/revolution (32K or 64K). At this rate, with 3000 rpm speed - or 0.02 revolution/sec - the encoder produce pulses at 2.73 MHz (if 32K resolution is selected) or 5.46 MHz (if 64K resolution is selected). I looked in the datasheet and user manual of PCI 6515 (http://www.ni.com/pdf/manuals/372172b.pdf) but I couldn't find whether PCI 6515 digital inputs can successfully acquire or detect the encoder pulses at this rate.

I really appreciate your help.

Thanks.

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NI Module Model Numbers

June 13, 2018, 7:25 am
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Hello Everybody,

I am trying to control and monitor

1. temperature (25C to 1400C),

2. measure vacuum pressure,

3. measure and control DC voltage (300V max),

4. DC current (11 amps max) 

5. thermal and optical camera to capture pictures.

So I need to know the individual models for these modules that will be compatible for these purposes and with the NI 9172 DAQ.

Please help! Thanks!

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NIDAQMX Python - Setting an output to High Impedance (High-Z) on USB-6001

June 13, 2018, 1:39 pm
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I have a USB-6001 and need to toggle an output between '0' and 'High-Z' and have tried the following methods with no success:

  1. Using an analog output
    1. ao_output_impedance=1.0e9. I get error message that this option is not available on my device
    2. ao_voltage_current_limit=0.0. I get error message that this is also not supported.
    3. So how can I turn off an analog channel?
  2. Using a digital output
    1. First I do 
       chan_fast_en_l= task_do.do_channels.add_do_chan("Dev1/port0/line0",line_grouping=LineGrouping.CHAN_FOR_ALL_LINES)
       task_do.write(True,auto_start=True); 
    2. chan_fast_en_l.do_tristate
      This has no effect and also gives no errors. The documentation says I must 'commit' this change, but I don't know what a 'commit' is and failed several attempts like "task.action.commit=0".
    3. chan_fast_en_l.do_output_drive_type=DigitalDriveType.OPEN_COLLECTOR;
      I get no errors but the pin continues to output 3.3V
    4. Is there a write keyword like TRUE, FALSE, HIGH-Z?

I'd really appreciate some assistance! If you could help for digital and analog, with some sample code, then that would really help me and others I'm sure.

 

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What should be done to achieve a function similar to active matrix (4*4)?

June 15, 2018, 12:45 am
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Dear ALL,

 

I am using PCI-6221 and window 8 64bit with connector-CB-68LPR and cable-SHC68-68-EPM. I need 8 digital inputs and 8 digital outputs.

I am new to Labview. I try to achieve the function similar to active matrix (4*4 matrix, each row got 4 pixels):

1.With the scan driver 1, I hope to scan and open row 1, row 2, row 3, row 4 and then again from row 1...the other rows will close except the scanning one, the timing1 should be adjustable;

2.With the data driver, I hope to generate 4 bit digital data (each pixel should have 16 levels of voltage) to each pixel of the open row with reference voltage from outside.The time period should be synchronized with scan 1 and include it（larger than the scan driver 1）

3.With the scan driver 2 which is used to measure voltage. Because the scan driver 2 is used to measure, I hope it can be used anytime I need it.

8 voltage outputs will turn into digits through ADC on breadboard and then send to labview.

 

Could you please give me some advice on this design?Thanks!

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NI 9474 24VAC

June 18, 2018, 7:08 am
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Good morning,

 

I have an NI 9474 module that I would like to use to control some sprinkler solenoid valves. the solenoids require 24VAC. I see in the documentation for the 9474 that it specifies up to 30VDC, but doesn't mention anything in regards to AC voltage. 


I have to ask, even though it is not stated, will the 9474 work with 24VAC? 

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Recomended module to send power(12v or 24v) to 3 wire PNP sensor and receive the signal with cRIO.

June 18, 2018, 12:07 pm
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Hello guys,

I would like to know what is the module I could use to connect a 3 wire pnp sensor with cRIO.

I want to provide power to sensor and receive sensor signal in a digital input (like a sinking input).

Is it possible or I have to use an external power supply? In that case what is the recomended power supply from NI?

 

Thanks in advance.

 

 

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PXI-7853R analog outputs failure

June 21, 2018, 3:25 am
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HI,

I am using a PXI-7853R to generate output signal with Veristand, I started working with the new device 2 months ago and every thing was fine and I could  generate signals using AO0, AO1, AO2 ......AO7.
But starting from yesterday AO0 and AO7 are no more working, I can't see the signal that I want to generate with the oscilloscope and the photo of what I am visualizing in the oscilloscope from these two outputs (AO0 and AO7) is attached, and the visualization is the same even when I am not generating any signal.

I can't understand what is happening especially that the other analogue outputs are working well.

I am asking if the device is damaged or if it needs repair, or if any one can help me to solve the problem.

Any advice is appreciated and thank you for helping or trying to. 

20180621_121737.jpg

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NI-6009 200 Hz noise

June 22, 2018, 7:28 am
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Hi!

 

I am using a NI-6009 and I am experiencing a 200 Hz noise in the environment. I read an old post when someone was experiencing something similar with a NI-6501. But the content of the post was removed. Any idea on how I can solve the problem? 

 

Thanks,

Michela

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How to write 4 bit (0000~1111) digital data of 4 interfaces to a 4*4 matrix of pixel circuit with resistors (like active matrix) row by row with my DAQ?

June 25, 2018, 8:30 pm
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Dear ALL,

 

Hi there!

 

I am new with Labview 2016. I am using DAQ PCI6221. I hope to write 4 bit (0000~1111) digital data with 4 lines to a 4*4 matrix of pixel circuit with resistors (like active matrix) row by row. Each line should send serial data and then transfer to analog voltage.

 

Questions:

1. Could you please show me how to achieve the functions? Is there any snippet or example?

 

2. How to control the timing?

 

Thanks very much!

 

Best,

Jason

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How Do I Connect My Phone and Tablet to a USB Connector Drive?

June 26, 2018, 12:42 am
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I need to access a lot of files stored in my flash drive. But my laptop just broke down and I can’t seem to find a PC to plug my USB into. Is it possible for me to access my files through my Samsung phone or Samsung tablet? If so, would I be needing special USB connectors or adapters, and what are they? I hope you can help me with this one. Thank you.

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USB 6008 Digital output high is only 0.07 V

June 27, 2018, 5:03 pm
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My USB 6008 Digital Output high is limited at 0.07 v and it is consistent.

 

I tested all digital lines, analog input reads them at same voltage. Compared the voltages on multimeter to see if ai pins are alright. The voltage reading matched measured ai values. If I disconnected ai- from gnd, the voltage floats by 1.4v, as mentioned in the manual. The output sources 5v and 2.5v are also not showing their rated voltage.

 

I tried disabling "USB selective standby". Observed no change in output.

 

I want to know if there is anything else I can do to verify if its working... or is it broken?

 

Thanks

Vijay

 

 

 

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Detect state change in Din without loop - arduino Linx

July 2, 2018, 3:56 pm
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Hello, I'm using arduino mega with Linx, I need to read the state of a Digital input , if there is a status change (0 to 1) then other part code is triggered. Of course is possible make it with a while loop and reading the input.  But I wonder if is possible to do it for example with a event which is triggered automatically when there a status change in the input. In microcontroller programming this can be done easily with interruption by status change. The reason to not to use a loop constantly reading a input is resources consumed by this way. 

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C68-C68-D4 Temperature Range

July 5, 2018, 12:27 pm
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Hello, 

 

I tried to solve my doubt searching for datasheets or some other support document in the NI website and the Internet using Google, but I have not been succeeded. So I came here in hope that someone has this information, or know where to find it.

 

I need to use the C68-C68-D4 cable to interface the PXIe-6535 module with a DUT that will be allocated inside a thermal chamber, which temperature will vary between -40°C and 85°C. I would like to know if this cable can be handled with these temperature values, without being damaged? Also, I would like to know what is the temperature range for this model?

 

Thanks and best regards.

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ISC 1781 Smart Camera Not Sending Output in Vision Builder

July 12, 2018, 7:09 am
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Hello,

I am using an ISC 1781 Smart Camera with Vision Builder 2015 software installed with the starter kit I/O board. This is a brand new setup.  

 

I created a recipe in vision builder 2015, but when I get to the "Generate Pulse" step, I am not receiving any outputs at my board, and therefore not to my output device. No matter how what settings I use for the generate pulse step (drive high/low, generate single pulse/ start pulse generation, pulse on completeion of X/ generate pulse when setp runs), I cannot receive an output to the board.

 

We have tested the ISO outputs 0, 1, and 2 with a voltage meter, but do not receive a signal from the camera.

 

I have used the NI 1772 cameras with a similar setup, and had no issues. However, this model was discontinued, and we had to upgrade to the ISC 1781, but cannot get it working.

 

Any ideas?

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Yokogawa Ethernet Wt300e Ni MAX

July 12, 2018, 8:05 am
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Buen día para todos,
Trabajo con labview 2016 para tomar lecturas de un Yokogawa wt3000e y un WT1800 les comento que al agregar el dispositivo al Ni Max por ethernet el Wt1800 se detecta sin problema pero el wt300 no me marca que este conectado aun cuando al hacerle un ping si contesta ok

instale el Nipackage manager y desde ahi agregue el drive WT3000
Alguien sabe si debo bajar un drive adicional ?  o alguna sugerencia de algo que este pasando por alto

saludos y desde ya gracias

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Change detection on USB-6001?

July 15, 2018, 11:15 am
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I want to use a USB-6001 (not yet in my possession) to detect when a digital signal changes state. It's okay if I miss some state changes, but at any time I check (it doesn't necessarily have to be event-driven), I need to know if a state transition has occurred since the last time I checked (and I also need to know the state at the time). My use case is a proximity sensor--I need to know if at any time a device has moved out of range (even if it has moved back into range by the time I check it) so I can abort a process.


Software polling of the digital line state could potentially miss transitions. It seems like using DAQmx's change detection is the ideal solution, but the USB-6001 does not support this. I considered using a counter--each time I check the counter I can tell if a state transition has occurred by checking to see if the count has changed. But as far as I can tell, it can't tell me the current state. Furthermore, the DAQmx example "Counter - Count Edges.vi", does not list the USB-6001 as a supported device--is this really true? The example gives no errors when I run with a simulated device, and I can't think of a simpler counter application that the USB-6001 could support.

 

Another possible solution would be to use the DI signal as the clock source for a timed event structure. I'm not exactly sure how to do this, but I'm pretty sure the USB-6001 does not support this. Also, I think it may not be possible to determine the DI (Clock) state.

 

Does anyone have any suggestions for how to do what I want to do with a USB-6001? If it's not possible with a USB-6001, what would the best available (USB) device that could do it?  It's hard for me to figure out exactly what capabilities a board supports.

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Triggering Data Acquisition with continuous 5V source, NI 9401, and NI 9263

July 24, 2018, 6:09 am
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This is my current VI. I have a sensor that sends a mA signal and is converted to height and two thermocouples that display in real time. I have a cDAQ 9185, an NI 9207, an NI9210, an NI 9401, and an NI 9263. I need a continuous 5V source so that when the wire is connected, the input reads it as a trigger and starts acquiring the data for the amount of time predetermined in the time target. I have been struggling with this for awhile and I am new to LabVIEW.

Also, I need to connect another trigger the same way but this time when the wire is connected and the 5V is read back to the DAQ, I need it to make a mark on the graph each time it is hit to mark a period of time within the data acquisition.

Thanks!

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Sample Rate of NI 9472 DAQ being slowed by an unknown variable

July 24, 2018, 12:44 pm
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Hello,

 

I would like to first state that I am very new to LabView and DAQ devices.

 

I am having an issue that concerns the NI 9472 DO DAQ device.  I am using this to control a heating element using PWM.  I read the element temperature using a type-K thermocouple wired to the NI 9219 AI device.  Using a PID loop I acquire my DC %, and from that % value I can use PWM.  

 

The issue is this: when I run my VI, the PWM graph shows no signs of functionality.  At first it did work, but was very slow.  My solution was to create a separate while loop and this fixed the issue.  Though upon completion, it didn't work, but was able to run.  

 

I tried deleting the Analog to Digital VI as well as the DO DAQ Assistant, and that solved the issue.  But obviously I need those functions in order to achieve desired results.

 

I'm thinking the issue lies within the DAQ device or my chosen method of going from digital waveform (source) to the 1D array digital waveform (sink) when connecting the A to D VI to the DAQ Assistant.  

 

Any ideas?  I'm sorry if this is confusing, I'm still learning very much.  

 

Thanks!

 

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