Pressure sensor interface

Hi,
I am trying to building an application to test pressure leak on my instrument. I am using (30) MPXH6400A pressure sensors interfaced to NI USB-6218 DAQ card. I looked at the signal level compatability for the outputs from pressure sensor and input to DAQ and everything looks ok. I am a newbie in using Labview and I am trying to build a .exe for manufacturing to test my instrument on the line for any pressure leak. I figured there will be some starting point which I could use to build my application. The way that I envisioned the program would work: Interface each output from the sensor to a seperate A2D channel in DAQ and have a threshold in the software. If it passes the threshold light an LED with green showing the instrument has passed pressure leak test or if not light the led "RED". I would really appreciate if I could get some pointers to where I could start.
Thanks

Help\Find Examples...\Hardware Input and Output\DAQmx\Analog Measurements\Voltage : will lead you to lots of examples
Pick this one: "Cont Acq&Graph Voltage-Int Clk.vi" as a start
On your computer, you should find it here C:\Program Files\National Instruments\LabVIEW 8.5\examples\DAQmx\Analog In\Measure Voltage.llb\Cont Acq&Graph Voltage-Int Clk.vi
Like Dennis said enter "Dev1/ai0:29" for 30 consecutive channels on a Device named "Dev1".
If you named your USB DAQ something else, use this instead of "Dev1" of course.
Process the "Data" output from the "DAQmxRead" vi as requested to turn your 30 led's red or green.
Attachment SNAG-002.jpg is just a very rough idea on what you could do.
Average 1 second data and compare it with some threshold levels.
Message Edited by Alain S on 01-03-2010 03:13 PM
Attachments:
SNAG-001.jpg ‏292 KB
SNAG-002.jpg ‏45 KB

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As GerdW mentioned in the other post you might want to speak with a NI applications engineer. If this is a school project of some type and/or you just want to spec everything yourself then you certainly can. Your first step is to define all the physical parameters of your devices. So you need to know what kind of stepper motors you need based on the required angular resolution, torque, etc. What kind of pressure gauge will you use? What type of output will it provide you (simple voltage, pulse train, full USB interface)??? What kind of switch will you use. Can it be controlled by low-current TTL or will you need a driver or relay?
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SCXI 1520 for potentiometer type pressure sensor

I am usig 1520 for bridge type pressure sensor data acquisition.
I have a requirement for potentiometer type pressure sensors. The sensor is a potentiometer that needs 5V exciation.
+---------------- Exc+
|
|
+--+
| |
| |
| |<-------------- O/p+
| |
| |
+-+
|
|
+---------------- Exc-
I was wondering if I could use 1520 for interfacing with such sensors?
I am hoping I can short P- and S- lines and connect to Exc-. P+ would be Exc+ and S+ would be O/p+.
The resistance between Exc+ & Exc- is of the order of 1-5 kOhm. So the current drawn from the excitation supply is of no concern for the 1520, I believe.
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Dear Cas,
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Hello Everyone,
We have a FPGA board NI cRIO-9073, a temperature module NI 9217 and a pressure module NI 9203. Right now we have problem with saving the data from pressure sensor. I succeed in getting and saving the data from the temperature sensor. Then I just simply modify the FPGA VI and host VI of the temperature function block which are shown in the attachment files.But I get an error saying I cannot connect two different data types.
Could anyone here give me a help on this?
BTW: we are using a 2 wired pressure sensor with 4~20mA. The brown one is +Vcc and the white one is GND.I connect the white one with the COM of NI 9203 and the brown one is connected to AI7. DidI make a right connection?
Thx for any help from anyone!
Attachments:
pre_tem.JPG ‏36 KB
pre.jpg ‏35 KB

Hi, I get this error message:
Write to textfile: function contains an unrelated or improper connection.You have combined two different types of connections among each other.
At least one entrance of the function required for their operation, is open or not properly connected, the connection scheme is illustrated in the context help.
They have combined two different types of connections with each other. This connection is not possible because the data types (such as "numeric", "String", "Arrary" or "clusters do not match"). Open to see the contextual help at what must have a data type for the connection. The type of data source (fixed) costs. The type of data is dynamic data.

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I do not know the type of sensor you are using. But pressure transducers may have a very low output voltage(in the mVolt range). They also need an excitation voltage. Here is an introduction. http://focus.ti.com.cn/cn/lit/an/sloa034/sloa034.pdfThen working with pressure sensors I always use 3 stages in the circuit.
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Hi all,
I have a problem in calibration of pressure sensor.In attachment i am sending the data-sheet of the sensor and the block diagram i made.I used linear fit to calibrate.y axis range:0-100 bar x axis range:0-10VDC
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Regards,
Attachments:
H72300.pdf ‏380 KB
pressure read 2.vi ‏33 KB

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Greetings from Germany
Henrik
LV since v3.1
“ground” is a convenient fantasy
'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'

Which Xperia phone models have pressure sensor?

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Tried CISCO IDS sensor 4250-XL with the following 4 interfaces:
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Attached is the sh tech

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Hello everyone,
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Hi Wapz,
My name is Mitchell Goon, from National Instruments Technical Support.
You will be able to download a detailed calibration certificate for your device from the NI website. You can refer to the link below for more information on how to obtain the Calibration Certificate:
http://digital.ni.com/public.nsf/allkb/7695C93D283BC1A086256B1800631DCF?OpenDocument
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http://www.ni.com/white-paper/3816/en/
http://www.ni.com/white-paper/3639/en/#toc4
Additionally you may wish to refer to this tutorial on how to setup your DAQ device for pressure measurements:
http://www.ni.com/tutorial/7138/en/
I hope that this information will be useful for you. If you require any further assistance, please do not hesitate to contact us and we would be more than happy to assist you.
Kind Regards,
Mitchell Goon
National Instruments
Applications Engineering
www.ni.com/support

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Hello,
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Attachments:
Baratron2.6.vi ‏524 KB

IF you are running the Microsoft Windoze Operating System (ie: XP), it should be located from the Start Menu:
All Programs > Accessories > Communications > HyperTerminal
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Hello all!
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#include <windows.h>
#include <vector>
#include <iostream>
#include <fstream>
namespace
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int main(int argc, char* argv[])
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std::vector<float> dataArray(packetLength, 0);
std::vector< std::vector<float> > buffer;
int framesReceived(0);
//Main loop
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for (int i = 0, n = buffer.size(); i < n; ++i)
for (int j = 0, m = buffer[i].size(); j < m; ++j)
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How could I do something similar using LabView?
How could I use the DLL file in order to do this?
Any help would be greatly appreciated.
Thanks in advance.
Best regards.

Pressure sensor failing to provide reading.

Hi all,
I'm using an RS comoponents pressure transducer UK part number is 461-323 http://uk.rs-online.com/web/search/searchBrowseAction.html?method=searchProducts&searchTerm=461-323 trouble is I can't seem to get anything from it.
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Hi docb
How are you trying to get this sensor information into your computer?
What National Instruments hardware are you using?
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Regards
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National Instruments UK & Ireland

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Hi all!
Hope you are doing great!
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Measurement of the dynamic pressure by IEPE sensor

Hello, I work on cylinder pressure measurement in combustion engine. I have a piezoelectric pressure sensor with charge output 1 pC/psi and an inline charge amplifier 20 mV/pC
what gives overall sensitivity 20 mV/psi.
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Here are the parameters: Sensor Maker: Dytran, type: 2200C5
Charge amplifier Maker: Dytran, Type: 4705M5, charge amplifier is of an IEPE standard.
I have attached their specification cards too.
In the file signals.jpg you can find my calibration experiment record. I was applying step-like pressure (blue line) to simulate rapid pressure increase. the value was 120 bar. I was expecting that the answer signal will be a pulse proportional to the step pressure. I have noticed that the answer depends from how fast the pressure increase, that means from the derivative of the pressure signal. I will attach one more file where you can see that it is proportional to the logarithm from that derivative.
Honestly I do not understand it at all now.
Attachments:
4705M5.pdf ‏91 KB
sensor 2200C.pdf ‏24 KB
signals.jpg ‏96 KB

Pressure sensor interface

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