pressure measurement

Similar Questions

• stop DC-source after awhile and then begin the pressure measurements

  I don't think that what I want is so difficult, but I have very little experience with labview.

  I generate a continuous voltage for a period of time. After the time of the source voltage must become zero and pressure measurements must begin.

  In vi, I did the steps start at the right time, but the source never generates a voltage.

  I placed a picture of the diagram as an attachment. There is nothing in the case if the value false.

  The while loop ends after the time to reload, and then the case would become true.

  The part related to PXI1Slot2 for the source and the part related to PXI1Slot3 for measurements. (But as I said, there is no problem with my measurements, the DC-source is my problem)

  I know that I can use the source because I can do generate a voltage if I place the part related to PXISlot2 on its own to a vi.

  Hello

  Both sides in the case structure should arrive in a certain order? As they are it is unclear who will take place in what order.  If they must be in order, use the wire of the error to force the order or try a sequence structure to put them in order in consecutive images.

• SMU-6363 pressure measurements

  Hi guys,.

  First post here. I tried to search first for documentation but empty is come.

  I use the analog inputs on the 6363 map to make some measurements of voltage. I have 2 questions:

  1. I know that the channels are limited to +/-10 volts for entries. I have a 25 Volt with a resistance line series regular (50mOhm) sense. I want to do a differential measure resistance across with 2 analog channels. The real tension between the two points will be in the range of mV, but the unique finished voltageon each will be ~ 25 V. Will this work?
  2. In a similar configuration, but on a 5 volt line can I build a differential measure through a resistance of sense current using 2 channels and then turn around and use one of these same channels for a single measure is complete wrt gnd?

  Thanks for your help!

  There is a row in the datasheet that States

  Maximum voltage of work for the analog inputs (signal + common mode)

  ±11 AI GND v

  So with a 25V common-mode voltage, you will hurt your card.  The 5V line should be fine.

  If you look at Digikey, there are chips specially designed to detect a current shunt.  The differential voltage amplifiers will become a simple nerve from the ground.

• the basis of my time scrolls not (in my blood pressure measurements)

  I have a DC 5v pot connected to my USB DAQ 6008. In labVIEW when I run it I get my voltage output as expected but the time base does not scroll it remains fixed. When I change the axis scales the output voltage varies even in the first second only. Does anyone know what is the problem?

  I don't think you can ignore the timestamp which is part of the dynamic data. I never use dynamic data and I hope that I am never placed in a situation where I have to.

  Eventually, a difficulty for the elevator VI is in the attachment. Since you have wired some scalar indicators data, TI EÉ seems not you care about 1000 samples so I used a function average to get a scalar value at least a certain meaninig. Then I converted to a real scalar.

  If you want to paste the dynamic data, you cannot use the function bundle in VI of the gear. The correct function would be the merge of the signals feature.

• Complete noob - would like to measure the voltage to manual start and stop

  Hello

  As the topic says I'm a complete noob when it comes to programming OR.

  I'm looking for someone to point me in the right direction

  Installation program:

  Windows8 office

  Visual Studio 2013

  NI 6255 PCI data acquisition card

  Block connection OR SCB-68

  What I want to do:

  I want to write a console application to measure the voltage on the signal ai16

  -I want to be able to start and stop the application manually

  -I want to be able to pressure measured in a CSV output.

  Where I am:

  I compiled and ran the example "NOR-DAQ\Examples\DAQmx ANSI C\Analog In\Measure voltage.

  It is said that I have "collected" samples but I don't know what that means, as I do not see an output file...

  What I don't understand:

  Samples - I do not understand cela or know even where to start

  How can output file - I get the file to save the collected data.

  Thanks in advance

  Chad

  Hi Arron

  Thanks for the link, unfortunately, it has not helped because the instructions were for Visual Basic and C++ not. It was my fault for not putting the language of prog that I need help in my original post.

  However, I started to find help on this link: http://www.ni.com/tutorial/5409/en/

  -With the help of NOR-DAQmx in text based programming environments

• read the signals of pressure using signalExpress

  Hi, I have no pressure option under DAQMx Acquire-> Analog Input
  menu when I add a step to acquire pressure signals in SignalExpress 4.0.
  Everyone knows what additional module I need to do? Thank you. Cong.

  You may need to upgrade your version of DAQmx.  The type of pressure measurement was added in DAQmx 9.1.

  Here is a link to our latest DAQmx, 9.3:

  http://Joule.NI.com/nidu/CDs/view/p/ID/2337/lang/en

• Synchronization of data from different sample of data acquisition rate

  I use a high RT 8135.  I'm sampling of signals from analog pressure thermocouples to 20 ms and 10 ms.  I use the stream network to transfer the data from the SMU on my host.  I would like to be able to synchronize the timestamps of all data to the 1ms sampling note and record in a file.

  Search in the file my sampling data 10ms end timestamp does not match the timestamp of 20ms, missing data... I know you have empty queues to get the rest data but is possible to interpolate any data to adapt a unique timestamp?

  Thank you!

  Hi aokada09,

  Looks like you are facing problems resulting from parallel execution two loops you have.  There is nothing necessarily bind the two loops together, so that each of them an iteration at the rates you specified, but are allowed to start each software (sort of random) dictates that they start.

  To get a solid synchronization, share a sample between the two measures clock, but run the sample clock at 100 Hz for 50 Hz for thermocouple measurement and pressure measurement.  You should be able to use shared inside the SMU chassis backplane clock.  This will be as close as possible to synchronize without using a card of timing.  The only real source of delay/tilt between readings at this point is the physical distance that must travel the clock signal. This will not lead to steep, but there will certainly be some (probably on the scale of the high-nanoseconds or microseconds bass).  This article gives more information about the synchronization and the sample clock:

  http://www.NI.com/white-paper/11369/en/

• Variation of thermal EMF of the PXI-2530 modules

  This message/question is a companion of my the most recent message in another thread.

  In addition to watching some resistance higher than expected that affected current measurements using modules PXI-2530 multiplexer 4W topology, I saw systematic variation in track-to-track blood pressure measurements. Tensions would increase gradually through the 16 channels in a configuration by measuring the voltage at the terminals a resistor 1.5 kOhm with 0.5 au crossing (75 uV). I've identified that the thermal EMF of the reed in the PXI2530 module switches is on the same order of magnitude of these measures and set out to quantify the differences EMF thermal track-to-track between my three modules.

  Test method: I have a TB-50 which is configured to mux the signals of tension for a DMM. I connected each of the four DB-50 one cable of 176 pins to this block and collected with a PXI-4071 pressure readings set to 7.5 digits precision in the range of 100 mV and > 10 GOhm impedance. For most channels, it took several minutes for the voltage stabilize - or at least appear that it was to stabilize.

  I enclose three graphs. Note that the vertical scale is the same on each.

  Data that triggered this survey was collected with MUX1, via connector P2 to voltage. The magnitude was not quite the same-probably related to the phenomenon of stabilization time, but obviously the worst group of channels three multiplexer modules.

  The three modules were all bought at the same time (about 2 years ago), but had only limited its use in the first year or more. The three now have various 'mileage' based on my use. But MUX1 clearly behaves differently two other modules. The

  I changed my test conditions to spend 0.5 au via a higher resistance to thermal EMF less important. The PXI-2530 sheets indicate that thermal EMF must be less than 50 uV. In most of my measurements, it is. But not for MUX1!

  Any thoughts?

  Thank you

  Jeff

  Hi Jeff,

  You can check that all the three modules are PXI-2530, not PXI-2530 b (while, as the PXI-2530 b parts slightly higher thermal emf)?

  Specification of emf thermal 50uV of the PXI-2530 is a typical value, is not a guarantee of spec.  See a few channels higher than the spec is not a cause for alarm, but it shows that we must take account of this in our measurement error.  Note that the industry standard for the technical measure thermal emf is to close the relay, wait a few minutes and then take a measure of tension.  For example, if you scan through a switch faster than a relay per minute or so, the thermal emf will be less predictable and stable.  A single module performs worse at these low voltages is not indicative that this module is a failure, etc. the module is fine.  Unfortunately, the reed relays have more emf thermal relay of the armature, mainly because of the many layers of metal in a Reed compared to a frame (each metal junction is a source of emf if these metals are not the same).

  Thermal EMF is proportional to the temperature, it may be interesting to note the position of the chassis of the less powerful module.  Placing hottest modules (scanners, Ara, RF, etc.) will reduce the thermal emf.

• Sort of the original data and creating a new channel

  Hello

  I have a channel called "engine speed".  This channel extends the numberic values between 0 - 3000.  I want to create a channel named "Op_Sensor_Desired_Pressure" is the same length as the "engine speed", which I am familiar with.  I want my fill my Op_Sensor_Desired_Pressure channel with the data I have.

  I attach a CSV file that indicates the speed of the engine with the Op_Sensor_Desired_Pressure value.  So what I want is when the engine speed is = to what is in my CSV file I want to fill my Op_Sensor_Desired_Pressure value with the specifications in my spreadsheet to.  Values that do not exist then I want to present with a "NoValue".

  I thought to use a dictionary but cannot make it work. (As below)   I've also attached a set of data that I use.

  Dim dict3, j, t
  Set dict3 = CreateObject ("Scripting.dictionary")
  j = chnlength (1)

  Dict3.Add '630', '1 '.
  DICT3. ADD '1010', '2 '.
  DICT3. ADD '1020', '3 '.

  Call ChnAlloc ("Op_Sensor_Desired_Pressure", j, 2)
  For t = 1 to j
  IF dict3. There are (ChT (t, "Engine speed")) then
  CHD (t, "Op_Sensor_Desired_Pressure") = Dict3.Item (ChnVal (t, "Engine speed"))
  On the other
  ChD (t, "Op_Sensor_Desired_Pressure") = "NoValue".
  End If ' dict3

  Next

  Hello J,

  I have advanced and added the linear interpolation between the 2 fit points closest to you at each measured engine speed value.

  Call DataFileLoad (RawFilePath, 'TDM')
  
  Call DataFileLoad (FitFilePath, "CSV")
  
  Set RawGroup = Data.Root.ChannelGroups (1)
  
  Set FitGroup = Data.Root.ActiveChannelGroup
  
  Set RawSpeedChannel = RawGroup.Channels ("motor speed")
  
  Set FitSpeedChannel = FitGroup.Channels ("motor speed")
  
  Set RawPressChannel = RawGroup.Channels.Add ("Op_Sensor_Desired_Pressure", DataTypeChnFloat64)
  
  Set FitPressChannel = FitGroup.Channels ("Op_Sensor_Desired_Pressure")
  iMax = RawSpeedChannel.Size
  
  XMin = CHC (FitSpeedChannel, 1).
  
  XMax = CHC (FitSpeedChannel, 2)
  
  FOR i = 1 TO iMax
  
    X = RawSpeedChannel (i)
  
    n = PNo (FitSpeedChannel, X)
  
    XN = FitSpeedChannel (n)
  
    IF X = Xn THEN
  
      Y = FitPressChannel (n)
  
    < xmin="">
  
      X 1 = FitSpeedChannel(n+0)
  
      Y1 = FitPressChannel(n+0)
  
      X 2 = FitSpeedChannel(n+1)
  
      Y2 = FitPressChannel(n+1)
  
      m = (Y2 - Y1) / (X 2 - X 1)
  
      Y = Y1 - m * (X 1-X)
  
    Else if X > XMax THEN
  
      X 1 = FitSpeedChannel(n-1)
  
      Y1 = FitPressChannel(n-1)
  
      X 2 = FitSpeedChannel(n+0)
  
      Y2 = FitPressChannel(n+0)
  
      m = (Y2 - Y1) / (X 2 - X 1)
  
      Y = Y2 + m * (X - X 2)
  
    ON THE OTHER
  
      IF X > Xn THEN
  
        X 1 = FitSpeedChannel(n-0)
  
        Y1 = FitPressChannel(n-0)
  
        X 2 = FitSpeedChannel(n+1)
  
        Y2 = FitPressChannel(n+1)
  
      <>
  
        X 1 = FitSpeedChannel(n-1)
  
        Y1 = FitPressChannel(n-1)
  
        X 2 = FitSpeedChannel(n+0)
  
        Y2 = FitPressChannel(n+0)
  
      END IF
  
      m = (Y2 - Y1) / (X 2 - X 1)
  
      Y = Y1 + m * (X - X 1)
  
    END IF
  
    RawPressChannel (i) = Y
  
  NEXT ' I

  I enclose a file TDV useful to show the correlations and the gap between oil pressure measured and desired.

  Brad Turpin

  Tiara Product Support Engineer

  National Instruments

• Update of waveform outside under VI

  Hello

  I have a fairly complex (for me!) program with several sub VI, pressure measurement loop calls main VI a VI void is a while, each value is plotted on the graph of the waveform is measured in real time. I want to display this graph in real time in the main VI. However the table of waveform in the VI main shows only the last delivered value of sub VI after the sub VI has finished its execution of the loop.

  Is there a way to configure the waveform table in primary VI to only show data in real time to know duplicate what the table VI of void?

  Thank you

  It seems simple enough.

  Refer to the map of waveform control (by right-clicking on the graph > Create > reference) and place it in the main VI Subvi. The sub VI must have a point of order of the same type. Within the Subvi, you can update data using a property node. If you want to update the chart in each iteration of the loop, use the node property inside the loop.

• Sequence of a good idea?

  After the search and read a few posts from forums, I understand using the sequence is probably not the best idea?

  I wanted to get some advice on the best way to address my problem.

  What I want to do:

  I intend to use the van der Pauw method and the hall effect to experimentally determine various parameters for a small sample of semiconductors.

  Right now, it's a lot of your time to make all of the BNC connections required by the hand that in all the totals to 24 or 48 connections to make.

  To speed up the process, I want to use Labview to control a microcontroller to control transistors which controls of the Tower relays who make the required connections. At the same time after each series of necessary connections have been made, a current source controlled by Labview must provide the necessary current, a voltmeter to read voltage. A total of six different sets of four connections to perform and voltage read for all six groups. This must be done twice, but since the equipment creating the magnetic field is controlled manually, I can just run the program twice.

  Recently, I learned how to control an arduino using labview and how to control the power source and the voltmeter using labview as well.

  So here's the sequence that labview should send orders:

  Digital I/o using 6-pin on arduino

  1. initially, all pins are attached below.

  2. first pin set high, while the rest remains low. This option turns on a transistor making it the first series of connections.

  3. the current source is turned on and provides a specified amount of current to the sample.

  4 voltmeter measures the induced voltage and stores this as a double or be it in something like a table.

  5 current source turns off.

  6. second pin on arduino set high, while the rest low and steps 3 through 5 are repeated until all 6 pressure measurements were recorded.

  7. the 6 measures must be exported to excel the file or Notepad or other.

  8. the same data could be transmitted to something like a different tab in the same program to perform the calculations to find the semiconductor, parameters of the sample.

  So now my question on the best way to do these things. I was looking through labview and found what is called a sequence of flat, but according to the forums it's supposed to be frowned upon.

  My other thoughts using some kind of combination of loops/case, but I'm not sure how to structure and what should be included or excluded from the loop. Other thoughts are maybe a timed structure. Another possibility is to create 6 different vi and calling it one by one.

  So basically the program run, and once completed, I need for each measure 6 voltage, preferably displayed in both a table and saved in excel/Notepad.

  SaintsFan says:

  So here's the sequence that labview should send orders:

  Digital I/o using 6-pin on arduino

  1. initially, all pins are attached below.

  2. first pin set high, while the rest remains low. This option turns on a transistor making it the first series of connections.

  3. the current source is turned on and provides a specified amount of current to the sample.

  4 voltmeter measures the induced voltage and stores this as a double or be it in something like a table.

  5 current source turns off.

  6. second pin on arduino set high, while the rest low and steps 3 through 5 are repeated until all 6 pressure measurements were recorded.

  7. the 6 measures must be exported to excel the file or Notepad or other.

  8. the same data could be transmitted to something like a different tab in the same program to perform the calculations to find the semiconductor, parameters of the sample.

  A state machine with these 8 States (and perhaps some assistance States: idle, stop, start, error, etc..).

  Basically a while loop with a case structure (one case for each State) and a State (e.g., enum) variable in a passage that. Look at the design templates provided with LabVIEW.

  (A flat sequence is too rigid for this. What happens if an error occurs in the #5 State? It has no way to go to a State of emergency. What happens if you want to stop in the Middle? What If a State fails and must be repeated.)

• increase buffer size

  Hi all

  I am currently taking 6 pressure measurements, convert and then send HAVE up to 6 current AO, so I'll have continuous samples for each channel. I got error 200609, which wants to increase the size of buffer when buffer selected size: 1 and Minimum required Buffer Size: 2.

  I tried to correct this error by adding the output buffer configures and adding the constant 2, then it gives me error 200524, saying:

  Scripture cannot be performed because the number of data channels does not match number of channels in the task.

  When writing, provide data for all channels in the task. You can also change the task so that it contains the same number of channels as the written data.

  Number of channels of task: 1
  Number of data channels : 2

  I was stuck for a few days, now try what is recommended in the forums... what should I do to get this program to work? Fastener is the program. I just started to work with Labview a few weeks, so I'm a beginner.

  Any help is greatly appreciated!

  Try to remove the sample VI on the task of output clock and write NChan 1Sample inside your loop to update outputs.

• response time of entry

  I have a hydraulic solinoid valve powered by a digital output on my hardware (USB 6012) DAQ holding pressure measured by a sensor which is read in an analog input channel. I need to measure and draw the necessary time to denergising the solinoid for pressure valve reach 0 i.e. 0v. the average time for this is 70mS, a time vi will be good enough for this or I have to use something else. All advice will be welcome.

  Look in the

  Output\DAQmx\Analog Measurements\Voltage of Help\Find Examples\Hardware entry and then choose it for example "Acq Cont & chart voltage-Ext Clk - Dig Start.vi ' as a starting point.

  The measured voltage is your pressure sensor

  The beginning of the search is you digital I/o that drives the valve

  Change what needs to be changed, but use it as a start...

  PS: There is perhaps a better in the list but I didn't check all the

• Problems with tracer bulb off

  Hello

  I have problems with a labview program in which IV of the data are collected using a potentiostat 600 ref of vanessa in a nested loop. The applied voltage intensifies in increments after each iteration. The data for each series are sent to a waveform curve each race as well. The problem is that it usually works perfectly when the tracer light is on (light bulb to the top toolbar), but will not take any data when turned off. There aren't usually any errors that appear in both cases and while I can see that the blood pressure measurements are produced when the light of the tracer is off, nothing does not appear in the graph.

  My first thought was that the program is simply too fast for my computer to be managed with the tracer off so I tried to add delays without result. I also tried to restart all connected, material, again to no effect.

  I enclose the program.

  Thanks in advance.

  Kai

  Hello

  I think it's better for your application use a single machine to States instead of three, because this way, you can directly connect variables and do not use local variables that can generate racing conditions in your program, which could be the reason why you don't take all the data when the light tracer is turned off.

  Concerning

• Increase the speed of acquisition of a coding of LABVIEW

  Hi people,

  I use digital USB 6509 advice to do some multiplexing.

  Then, I use USB-6255 boards to get some blood pressure measurements.

  The acquisition is a bit slow and I am trying to increase the speed.

  I enclose the code. If some have a few tips to increase the speed of vi and/or someone has some experience with

  These tips I would appreciate it.

  The code is attached.

  Best regards

  Rui Silva

  Rsilva wrote:

  Another point, if I may ask, are the startup tasks. The reason for the structures of the case is if tasks do not begin without the others.

  Structures of the case?  I don't see any business structure.  Do you mean the sequence Structures?  You don't need those at all.  Just spread the wire of the error (ie the use stream) to force your execution sequencing instead.