How much are the current and the voltage released from NI-9482 with the attached VI (simplest VI)?
The user manual of NI-9482 tells us the maximum current and voltage; 2.5A max at 30VDC, 1A max at 60VDC, and 2.5A max at 250Vrms. Is the maximum current applied with the simplest VI? How to control the magnitude of electrical current?
Hi All, I'm using an NI-6509 / PCI card to generate encoder pulses. All we do is write to the outputs every 2ms. It seems the write is a blocking call, and when we check the min/max time for a write is varies from 0.1ms to 1ms, sometimes we even get write times up to 2ms, which causes some issues.
So I have 2 questions:
1. Is there a way to make this call "non-blocking"
2. Why does the call take so much time
Here is the Python code to create the task:
Here is the write method, called every 2msec
Can anyone help , I need to send a digital output to the ni 9474DAQmx, I can get the unit to respond to the self test no problem. When I write to it does not respond. I have tried DAQmx native and DAQ assistant but to no avail. Here is one such attempt, with the wile loop greatly simplified.
I am working on trying to do some data acquisition with an NI-6545 installed in a 1095 chassis. I am supplying the chassis with a 10MHz reference source that is generated externally and also distributed to an A to D converter which uses the same clock as an encode clock. The A to D is constantly outputting digital data when powered on and being supplied the 10Mhz clock. I can supply the A to D with various high precision signals both DC and AC. When I do a continuous read, or any read, from the A to D over the 6545 then reassemble the bits, the data I am getting back has significant distortion or noise. If I mess around with my sample rate enough the distortion eventually goes away and will work fairly well until things are powered down and turned back on or some other setting is changed which causes the code to recompile. This is leading me to believe that it has something to do with the sample rate and reference clock synchronization or something. I need some ideas on how I can resolve the issues. I have attached how I am doing the acquisition now, and a few images of what the "noise" looks like.
I tried using HSDIO SClk Relative Delay, but with the sample rate set at 200MHz (which is what I want) that gives me +/-5ns and advancing/retarding the delay in 1ns increments didn't seem to have any effect at all.
One of the digital signals returned from the A to D is the clock signal it is using for the encoding, so I don't know if I could somehow use that for synchronizing my ref clock/sample rate to help eliminate delay or skew? Or if I can somehow trigger to read the data from the other DIO lines based on the clock signal DIO line?
Hello everyone.
I connect the NI9213 and 9474. I want to create an analog input from 9213 and digital output from 9474 (See in the attached file). But Channels in Data Doesn't Match Channels in Task.
Please help me with it.
Thanks a lot.
Hallo,
I have a problem with an 8451 SPI interface. It is connected to my system (labview 2019) and is recognized by the Measurement and Automation explorer - but then only for use of the digital I/O ports.
When trying to use the dedicated 845x drivers with SPI support in my labview program, no device is found.
How can I make sure that the device is available for the dedicated driver and not claimed by DAQmx?
(DAQmx is required for another instrument).
Hello,
I can connect the case structure to a single channel of digital output. Then I want to control two digital output channels at the same time, I connected the case structure to multiple channels, but it told me I connected two different types.
My question is: How can I connect the case structure to multiple channels?
Thanks a lot.
Dear All,
I want to control Line 0:2 at the same time. But after I set the True of the date array, the LED of NI 9474 was still not lighted.
How to solve this problem?
Thanks a lot.
Hello,
I am attempting to use an NI 9485 SSR module to control a set of Clippard electronic valves I am using for an experiment. Each valve will send a different type of fuel into a combustion chamber for my experiment.
My idea was to use an NI cDAQ-9189 with the SSR module connected to a PC, and write a python script that could send a true/false signal to the SSR in order to only turn on the one valve that I need with the others remaining closed.
However, I am unable to get a response from my SSR. The following codes are what I have written so far:
First, I used a script from https://github.com/ni/nidaqmx-python to test if my hardware was present.
import nidaqmx as ni
def query_devices():
local_system = ni.system.System.local()
driver_version = local_system.driver_version
print('DAQmx {0}.{1}.{2}'.format(driver_version.major_version, driver_version.minor_version,
driver_version.update_version))
for device in local_system.devices:
print('Device Name: {0}, Product Category: {1}, Product Type: {2}'.format(
device.name, device.product_category, device.product_type))
query_devices()
>> DAQmx 21.8.0>> Device Name: cDAQ9189-1CEF139, Product Category: ProductCategory.COMPACT_DAQ_CHASSIS, Product Type: cDAQ-9189>> Device Name: cDAQ9189-1CEF139Mod1, Product Category: ProductCategory.C_SERIES_MODULE, Product Type: NI 9485
Then, following the digital output example I was able to come up with the following code for actually sending a command to the SSR. Currently I am only working with one valve, so I only have port 0, line 0 occupied. I also have a voltmeter in parallel to my valve to check for voltage flow across the connection.
import nidaqmx
task = nidaqmx.Task()
task.do_channels.add_do_chan('cDAQ9189-1CEF139Mod1/port0/line0')
task.start()
value = True
task.write(value)
Which prints:
>> 1
Then I stop the task and close it.
task.stop
task.close()
The documentation states that the relay is normally open, so I assumed that I could just start the task and keep the relay open by setting it to True. However, I never see any voltage flow through the circuit, nor does the valve open/close.
I also attempted to test the panels using NI MAX, but got no response from the SSR either. Didn't matter if I set the port to high or low.
The final goal is to create a GUI application that would allow me to control all the valves in my system from my PC, without lugging around a huge switchboard and control panel. But as of now, I can't even control a single valve.
Can anyone provide me with some insight as to why my method is not working? I am pretty new to python still, so any help will be much appreciated.
Hello,
I am using DIO-6361. In MAX I can select the direction of the Digital lines from Input to Output and vise versa. How do I do that using LabVIEW?
For example I need to pull Port1/Line0 to low and then release that Line0. In MAX I can release the Line by selecting "All Input".
I use Digital output to pull Port1/Line 0 to Low
Would just reading the Line0 in LabVIEW release the line?
Thanks!!
Why there are additional numbers in the NI part numbers. For ex. original part number is 779975-01, whereas on the hardware it is mentioned as 779975E-01L. Any significance to those numbers. Are they same?
We are planning on developing a custom RMC board compatible with both the sbRIO-9627 and the sbRIO-9626. Looking at the connector pinout info on the respective user manuals of both boards we noticed that some of the pins labeled GND on the 9627 are labeled as RESERVED in the 9626 (for instance pins 2 and 8). My question is whether it would be fine to ground the pins labeled RESERVED in the 9626 as opposed to leaving them open or would we potentially run into some problems by doing that.
Thanks
Hello I'm having a bit of an issue with controlling a SSR with my NI-USB 6008. I'm trying to control a G3NE-205T-US-DC5 Control SSR with the Digital Output from the USB 6008 which as far as I can tell should have no problems providing the 5VDC and the SSR needs 5mA of Input current which seems to be pushing the capabilities of the Analog Outputs on the 6008 so I've instead tried to turn to the Digital Outputs. Connecting one of the outputs and GND directly to the SSR terminal 3 and 4 unfortunately only gives 1.2V on High and connecting and ammeter shows it giving .8mA, im not entirely sure the reason for this so I've attempted two wiring configurations from the 6008 user guide (seen below). In the first configuration I can't seem to get any pull up resistor value to work correctly, and in the second configuration (#1 in the second picture) I've also tried a few different resistor values in series but to no avail, the closest I got was having no resistor in series and getting 4.31 V and apparently 15mA through the ammeter (which as far as I can tell should have been enough to trigger the SSR and is somehow more mA then the 6008 can output. As a final note hooking the 5V and GND from the 6008 to terminals 3 and 4 of the SSR works as expected turning on the SSR. I think at this point I may just be missing something extremely obvious but any help is appreciated.
Hello,
Our student team was donated a NI 9485 module for our CompactDaq to control 7X 24V DC 105mA solenoid valves. I understand this is a 60V digital relay. After reading through the spec sheets and playing with the device in MAX and Labview, I'm not sure if/how I can trigger a simple switch of this DC signal to the valves. It looks possible per this snip from the getting started guide with the use of flyback diodes:
Looking at the example digital output VI NI provides, is it as simple as providing 0 or 1s to trigger channels?
Hello,
I'm new here but I've a modest question I'm searching a manual for the ultra old National logic analyzer VP-3620A? Can anybody help me in this way?
And no I don't want to buy a new one this is only for a waste project in a case that a CD-Player have a deathcounter build in so my suspicion.
Thank you &
Best Regards
Volker Hois
Hello everyone
I'm a new user of NI boards and am a bit lost with a dual stream_writers problem that I can't seem to find a solution to.
I'm trying to use a NI 6229 card with 2 x BNC-2090A (or even a single one) to send periodic simultaneous TTL pulses. One TTL pulse controls a speaker (plays sound waves) the other opens a port for a water release valve.
Independently, these two tasks are easy to do using the
function and these individual commands:
But when I run them in series (i.e. without closing the first one), I get this error when the second task tries to write:
I've added a 2nd BNC-2090A breakout board (see ao2 above) and I get the same error. I do have a 2nd 6229 card - but! my computer doesn't have any more slots to insert it into.
Should I not be using the stream-writers function to write TTL output?
Any advice is much appreciate! As I said, I'm quite new at NI + python configuration and a bit lost.
Thanks so much,
Catalin
Here's the entirety of my code, including a function that converts frequency values to oscillations playable via TTL pulse:
C:\Users\rg-fd02-user\anaconda3\envs\bmi\lib\site-packages\nidaqmx\task.py:98: ResourceWarning: Task of name "_unnamedTask<1>" was not explicitly closed before it was destructed. Resources on the task device may still be reserved. warnings.warn( C:\Users\rg-fd02-user\anaconda3\envs\bmi\lib\site-packages\nidaqmx\task.py:98: ResourceWarning: Task of name "_unnamedTask<2>" was not explicitly closed before it was destructed. Resources on the task device may still be reserved. warnings.warn( C:\Users\rg-fd02-user\anaconda3\envs\bmi\lib\site-packages\nidaqmx\task.py:98: ResourceWarning: Task of name "_unnamedTask<3>" was not explicitly closed before it was destructed. Resources on the task device may still be reserved. warnings.warn(
---------------------------------------------------------------------------DaqWriteError Traceback (most recent call last) Input In [6], in <cell line: 47>() 49for p inrange(duration): 50 water_Writer.write_one_sample(5)---> 51audio_Writer.write_many_sample(tone) 53# pause and give 0 pluse 54for q inrange(100000-duration): File ~\anaconda3\envs\bmi\lib\site-packages\nidaqmx\stream_writers.py:234, in AnalogSingleChannelWriter.write_many_sample(self, data, timeout) 229self._verify_array(data, False, True) 231 auto_start = (self._auto_start ifself._auto_start isnot 232 AUTO_START_UNSET elseFalse)--> 234return_write_analog_f_64( 235self._handle,data,data.shape[0],auto_start,timeout) File ~\anaconda3\envs\bmi\lib\site-packages\nidaqmx\_task_modules\write_functions.py:28, in _write_analog_f_64(task_handle, write_array, num_samps_per_chan, auto_start, timeout, data_layout) 18 cfunc.argtypes = [ 19 lib_importer.task_handle, ctypes.c_int, c_bool32, 20 ctypes.c_double, ctypes.c_int, 21 wrapped_ndpointer(dtype=numpy.float64, flags=('C')), 22 ctypes.POINTER(ctypes.c_int), ctypes.POINTER(c_bool32)] 24 error_code = cfunc( 25 task_handle, num_samps_per_chan, auto_start, timeout, 26 data_layout.value, write_array, 27 ctypes.byref(samps_per_chan_written), None)---> 28check_for_error(error_code,samps_per_chan_written=samps_per_chan_written.value) 30return samps_per_chan_written.value File ~\anaconda3\envs\bmi\lib\site-packages\nidaqmx\errors.py:191, in check_for_error(error_code, samps_per_chan_written, samps_per_chan_read) 189raise DaqReadError(error_buffer.value.decode("utf-8"), error_code, samps_per_chan_read) 190elif samps_per_chan_written isnotNone:--> 191raise DaqWriteError(error_buffer.value.decode("utf-8"), error_code, samps_per_chan_written) 192else: 193raise DaqError(error_buffer.value.decode("utf-8"), error_code)DaqWriteError: The specified resource is reserved. The operation could not be completed as specified. Task Name: _unnamedTask<4> Status Code: -50103
We has planed to use the USB-6525 but I was informed that there are more than 3 months delivery time.
Does anyone know any alternative?
Hi everyone,
I am using PCIe-7852R to generate square ware at 1MHz. I have two cable connect to the board
1. SHC68-68 EPM
2. SH68-C68-S
However, the output of two cables have different: (you can check in the figure).
could anyone help me to fix the problem with the output from SHC68-68 EPM?
I want the square wave output as SH68-C68-S
Thank you very much
I'm trying to trigger two separate relays to open and close a valve by sending a long ttl pulse on a button press. I get a constant 5v signal for 5 seconds on channel 0 but for channel 1, I only get a short pulse at the end of the 5 second run.
I have switched the channels and got the same result, with the relay on channel 0 working fine but channel 1 not. I have moved the wiring to different pins for channel 2 and it still didn't work.
I have 9401 with a 9924 screw terminal block on top, plugged into a cDAQ 9178 chasis. I have relay 1 wired to terminals 1 & 14 and relay 2 wired to terminals 3 & 16. They both use identical code with the exception of the channel selected.
