I have download Control design & Simulation module 2018 64 bit and installed it, and its activated.
but can not find the control design module in Control platelets. please help..
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Control design and simulation
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Shared Variables not found in Distributed Systems Manager
Hi all,
I cannot find my shared variables in distributed system manager even after deploying them. The shared variable engine error also appears if I try to access them inside VI. I have already tried un deploying and deploying, restarting LabVIEW and my machine. Any helps would be much appreciated. Please find below two screenshots for your reference.
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estimation of minimum response time of a PID controlled system
Hi all,
I have constructed a feedback loop to achieve displacement control, the loop is shown below.
About the process flow: the displacement sensor converts the displacement of the plant to voltage, this voltage is sampled by NI DAQ USB 6009 analog input channel, and the displacement is compared with setting displacement and then going through a PID controller which is achieved by a labview program, and PID program calculated output voltage is applied to the plant through USB6009 analog output channel.
About the system properties:
1. Bode plot of the plant
It has two peak, corresponding frequencies are 11000Hz and 71600Hz.
2. Bode plot of the displacement sensor is similar to a second order low pass filter, the cutoff frequency is 1000Hz.
3. The sampling rate for AI of NI USB6009 is 1000Hz,
The iteration rate of the labview PID program is 10ms,
The update rate for AO of NI USB6009 is 150Hz.
My question is, with all these system properties known, can we give an estimation of the fastest rising time if a setting displacement is set as a step input? It's better certain explanation can be given.
I don't expect to get a accurate number of the rising time, a rough estimation is enough (maybe the order of the rising time). I have actually tested the rising time, with the P I D parameters I used, the rising time is 60ms which is too large. I am working on reducing this rising time, but I think it would be better if I kind of know what is the best performance I can get with this system. That's why I started this thread here.
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omega flowmeter sensor daq connection
HI all,
I am taking over a project from a previous graduate student. So, I have to learn on the fly. I am having trouble with my Omega FDP3203-D-A flowmeters reading to Labview. The set-up worked at one point previous to my taking over. At this point reading is always the same, no matter what flow I set at the pump. The flow graph shows either 0 flow or the same max value, which is around 1500LPH. There are three flow meters attached so I suspect they are reading max flow which is 500LPH. Hence the reading of 1500LPH in the Labview front panel.
I am trouble shooting this and learning software and hardware as I go.
Does anyone have any ideas?
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NI MAX could not launch
Hi all,
I tried to launch NI MAX in win. 10 with the intention of detect a Keithley 2100 multimeter connected by USB. Since it is not Plug and Play device I click in "Create New...", but is prompted the screen that you can see in the pic attached. the device is detected by the Device manager (under the name "2100 Multimeter") but not by NI MAX (even if I click on Refresh button).
Please, does anyone any hint about this issue?
Thank you very much in advance.
Best regards,
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Feed my DUT with scaled signal
Hi everybody
i want to feed my DUT with a sweep signal scaled by a H(f) a transfert function that i have already calculate feeding my dut with a white noise and get the FRF of output and input so i have H as 1D array.
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Change the value of a boolean through other VI
Hi guys,
Imagine a case where I have a vi with a couple of sub-vi (A and B), each of it changes the value of a boolean.
I'd like to control the value of these booleans through the main one. The idea is to activate the boolean of A and 1 minute later activate the boolean of B, all of it automatically. How can I do that?
Many thanks 
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Review and update from typedef grayed out
I've encountered this several times, and have been able to recover from it through a (haphazard) combination of controls replacements, applying typedef changes, restarts, etc., but haven't figured out the root cause...
When the arrow breaks due to a "Type Definition 'something': LabVIEW cannot update from type definition without incorrectly preserving default values", most of the time this is simple enough to fix (right click the control or indicator, click "Review and Update from Typedef", click "Approve All", then go back and fix default values, if needed). However, sometimes "Review and Update from Typedef" is grayed out.
Under what conditions does this happen? When this does occur (for me, anyway), I'm usually replacing controls in a cluster typedef. Some other odd symptoms I see when this happens is that I either can't create a constant from, say, an unbundle by name, or, when I create a constant from a bundle by name, the constant is created and the wire is broken.
And, of course, what is the best way to recover from this (preferably not the haphazard key and mouse mashing I described in my first paragraph)?
Thanks,
Jim
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Running continously without looping
Hi,
please ignore. I think i figured it out. Just keep the random generator outside the while loop.
I am trying to write a program and I need this program to run continously without looping. For input there is a random generator which generates an array of random numbers. Rest of the program is showing those values in a knob meter. But there are constraints like only 8 knob meters are available but 12 values in the array. So I am using two buttons next and back. So initially it shows the first 8 values, pressing next shows the next 4 values in the knob meter. Pressing back takes it back to the first 8. If there are more than 12 values, the next and back will work accordingly but currently the code is only for 12 values in the array. But my problem is I used a while loop with stop button to run the program and then random generator keeps changing the values. Is there any way I can do this with just one set of random values, but the program should keep on working. Thanking You.
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Possible bug: NI_Data Type.lvlib:Get Cluster Information.vi
Consider the following demo (saved as LV2016 snippet):
When using the cluster element, the array returned by Get Cluster Information.vi contains the proper data type per element, but the values are reset to the default values (ie. 0 and "" respectively).
When reading the variant attributes, the values are present.
How can the values be extracted from the cluster?
Tested with 32 bit LV 2016, LV 2017 and LV 2018 on Windows 10 x64.
KR, Benjamin
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Timeout error using MODBUS RS-485 at cRIO-9039 and mod 9871
HI
I use cRIO-9039 and mod 9871 to communicate with RS-485, i alsow use modbus library.
Everything is working while i using USB/RS-485 converter but failed when i try to send orders to my device by cRIO.
I get only Timeout error (56).
I use Scan Interface.
I use port ASRL11::INSTR. I pluged the in the power to my device (mod 9871).
Do you have any idea why it happen?
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2.5 msec delay
Is there a way to delay each iteration of a FOR LOOP by 2.5 msec? The delay millisecs only allows whole numbers..I think.
Thanks.
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After upgrading, my built exe requires NI-488.2 Runtime?
I just upgraded from LV2016 to LV2018, and now my exe requires the NI-488.2 runtime. In LV2016, I only needed the NI-VISA runtime. Any ideas why? Any tips on what functions in my code are causing this requirement? I'd like to know so that I can try to remove/replace those functions.
The problem is that NI-488.2 runtime not only bloats my installer, but it installs some junk into Windows programs shortcuts which my customers will complain about. I am not using GPIB in my application. I am just doing some basic RS232 communication using NI-VISA.
Thanks, John
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Tank level control and its alarm
How can I fix this control system with an alarm that activates according to the next figure, in which, I'm reading real-time values? The problem is that I can't turn on the alarm during all the selected zones, it only turns on during the half of the curves that are out of the limits.
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Remotely debugging an executable ... no Error List?
I built an EXE for LabVIEW code. And the EXE works fine on my development machine. But it fails to run (broken arrow) on other machines. So I figured I'd use the remote debugging tools. I can connect to the remote EXE and see the panel and diagram (nifty!), but the Error List is empty. It says "No VIs with errors". So it won't tell me WHY it has a broken arrow.
At this point, I am just guessing why the arrow is broken on deployment machines.
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sb-RIO support on Labview 2018?
Hi all,
Does anyone know whether the Labview 2018 Robotics module will still support the old 'daNI' 'Robotics starter kit 2' based on the sb-RIO9632?
I have been using LV2015 up until now, but my University no longer supports this version, so I need to switch to the latest LV.
Many thanks
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Replicating Equipment Screen in LabView
How can I replicate the screen of a Tektronix oscilloscope DPO 2024 and a bk precision 4052 waveform?
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Call Library to generate user event with complex cluster.
What is the best way to have a dll generate a user event where the data type of the user event is a cluster that contains a double, an array of U8 and a string? I tried to pass the event parameter to the dll with the Type set to "Adapt to type" and the Data Format set to "Handles by Value". However this gives me the "Not enough memory to complete this operation dialog." and an error 1097.
Kind Regards,
Stefan
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How to translate language in subVI
Hi:
I am working in a German company and currently using LabVIEW program to communicate with laser system. I have some VIs sent by my colleague. However, the context help file is opened in German. I am wondering if there is any way you can easily switch it into English?
Thanks for the help.
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Windows Pop up message as a trigger
I want to write a Labview program to detect a windows pop up message from another app and at the detection of the message cause a conveyor which is connected to the PC to stop. I'm using a DT9817R Data Translation I/O Device as the link between the conveyor and the PC.
Does anyone know how I can capture the windows message?
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