Temperature Graph

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I want to have the ability to graph all 16 temperature channels at once.

I setup the TinScan example and through my research I found out if you lost 1 of your 16 inputs you would read open on all your TC's.

I'm trying to setup Tin and I need help.

I setup my array and my graph but need help connecting them through my block diagram

I want to be able to view all 16 channels graph.

Attached is what I have so far.

Thanks for your help.

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[Dennis_Knutson]

You didn't include the subVIs TIn or ERRMSG. Where did you get this example? Is it for use with an NI data acquisition board or something else? From the simple example (and hideously colored, btw), it looks like you are only taking a measurement from one channel at a time so you are doing a scan at all. I would suggest as a simple fix that you replace the while loop with a for loop and wire the channel input to the iteration terminal to scan through the channels. Autoindedthe results and use an Array to Cluster function (set for 16 elements) and wire that to a chart instead of a graph. A chart is designed to display data as it is acquired. something like the attached.

If you are using an NI DAQ board, then it's much simpler to set up a multi-channel scan. If that's the case, you should look at some of the shipping data acquisition examples.

Message Edited by Dennis Knutson on 02-02-2007 02:10 PM

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I used the XTin example that came with the UL software.

Attached is the Vi for the temperature1 (XTin)

Attached is the BJsample & BJsample1 (XTinScan)

Thanks

[Dennis_Knutson]

I have no idea what you mean by UL software but it seems that the VIs called bjsample and bjsample1 (for which you still didn't include the subVIs), plot all of the channels. What exactly are the problems you are having? since it seems that the hardware you are using is not NI, if it's hardware related or a problem with the software that the vendor provides, you may need to go to their technical support.

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There's a Universal Library (UL) for LabView users guide & measurement computing.  I'm using this as an guide along with the list of UL extension VI program examples to choose from in Labview 7.0

[Dennis_Knutson]

Okay, that explains where you got the hardware and driver but you still haven't really explained what the problem is with the scan example. It would seem to do exactly what you need. You provide a start and stop channel and the results for all channels are plotted.

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When using the Scan example if you lose a thermocouple (open,short) during testing all your thermocouple channels (0-15) will read -9999.99 in the text box and the graph will go flat.

[Dennis_Knutson]

I don't see anything in the posted LabVIEW programs that would cause this. I don't know anything about measurement & computing hardware but an open channel should not cause all channels to fail. You have again failed to attach the subVIs that do the actual scan TIScan or TIn so it is possible that there is something in there. A DAQ board measures voltage and in order to get temp readings, the voltage measured must be scaled. If the scaling is done in the missing VIs, then you should post them. If you run TIn on a good channel with a different one that is bad, do you get a correct reading? If you do, then I would suspect some code problem in the TIScan. The code I posted should allow you to use TIn to take a measurement on all channels.

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The code you provided worked great. I finally had a chance to work with it. I believe as you mentioned  there maybe a problem with TinScan.

With the code provided how can I slow down the scan time to maybe a 12hr format.

Do I use a timed loop or get date time in seconds?

Thanks again for your help.

[Dennis_Knutson]

To control the time between channels, you would put a Wait (ms) or Wait Until Next ms Multiple inside the for loop. To control the time between complete scans, put one or the other outside the for loop but inside the while loop. If you want the chart to display the actual time of acquisition, then you have to change the x scale properties and write the start time and loop interval to a chart property node. There is a shipping example called Real time Chart that shows you how to do that.