How to acquire temperature data from type K themocouple using AD595 amplifier and NI USB6008

[Wallace10]

Hello All,

I'm new on the site and kindly assit me on how to acquire temperature data from Type K Thermocouple (0 to +50 degC) using AD 595 thermocouple amplifier and NI USB6008 DAQ module. 

I will appreciate any similar Labview VI that includes alarm option and file storage option that can aid my understanding of the DAQ.

[Coq_Rouge]

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Wallace10 wrote:

Hello All,

I'm new on the site and kindly assit me on how to acquire temperature data from Type K Thermocouple (0 to +50 degC) using AD 595 thermocouple amplifier and NI USB6008 DAQ module. 

I will appreciate any similar Labview VI that includes alarm option and file storage option that can aid my understanding of the DAQ.

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Could you please be more specific about your problem. By posting question like this. It looks more like you just are fishing for an easy way out of some homework.

But anyway Labview has a lot of examples you may study. Go to toolbar and help. Select Find examples. Then search for daqmx. If you have any question please post again.

[Wallace10]

Hello Coq,

                 Thanks for your response. I have gone through the Labview NI Examples DAQmx vi,but i found out that the VI used mostly polymorphic vi different from the express vi i understands and more familiar with. My problem now is how to include Alarm and file storage option for data logging editting NI DAQmx "Cont Acq Thermocouple Sample-Int Clk.vi"

[George_P_Burdell]

Wallace10-

What type of file are you trying to create with your data?  You can probably use the Express VI “Write to Measurement File”.  If you need something more robust, you may want to look at the example “Write TDM File.vi”.

As far as your alarm, what are you trying to get the alarm to do?  Please provide more information.

[Wallace10]

Hello George,

                    Thanks for your information. Sorry i av been offline for a while. I have made a good progress on the data acquistion,i'm using write to measurement file vi (MS Excel). As for the alarm option, it should indicate a warning for above Max and below Min value alarm setting. I was unable tomake use of one boolean LED indicator for this purpose,but i do get a good result when use different LED each for the Max and Min value. Note the temperature measurement is for ambient temperature.

Also,i will need to capture and fit a transient response to a step temperature change with this model y=a*(1-exp(-b*x))+c , using  "Gate and Trigge"  & "Curve Fitting" express vi. I have been having problem to develop a labview vi to use for this aspect of the project.

Kindly check the attached vi for your contribution and how this can be modified to achieve the curve fitting task

[Asad_Tirmizi]

Alarm generation can be implemented using a boolean LED. U said that u were having good results using two boolean LED's. U must be using one for the max temp and one for the min temp. If u want to use one LED for both warnings u should use the "select" in the "Comparison" tab of "programming" functions. i did a similar project during my training phase and if i were to advice you on alarm generation i would ask you to attach a sound file( Buzzer)  with it aswell. Makes the alarm much more practical.

Message Edited by Virtual_Hornet on 10-20-2009 02:07 AM

[Wallace10]

Asad,

         Thanks for your response,i had tried using the select vi before now but could not get the desired result as there was no change from the LED at either temperature. I will give it a go again and see if i will get a positive result this time around.

Please,i will appreciate any additional information on how to get the sound buzzer attached to the VI. Also still hanging on the curve fitting for the transient response.

Regards,

Lawal

[Asad_Tirmizi]

Ive made a simple VI which mite give u an idea on how to connect a buzzer with ur boolean indicator, In this VI whenever the results go underneath the threhold of 2 the beep sounds. You can play with the frequency and attach multiple beep sounds to make the alarm look as deadly as u can :). Please find it attached. I cudnt see ur VI because i use a previous version of LV. Lab View 8.2 to be exact. Kindly save it in 8.2 format for me and then attach.

Have a good time.

Message Edited by Asad_Tirmizi on 10-22-2009 01:07 AM

[Wallace10]

Thanks for that useful info. Quite helpful! Still could not get the "select vi" fixed for the alarm option(Tmax and Tmin). I only get the desired result while on the temp above Tmax (i.e above 30deg) and within the range of 20 to 30deg. But no positive result when temp falls below Tmin of 20deg.

I av re-attached the vi in LabVIEW ver. 8.2

[JeffL]

I think your logic is a little broken in your VI. Something more like this is what you want:

Message Edited by JeffL on 2009-10-22 04:12 PM