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Continuous Loop Error

I have a program that calculates wet bulb from a few user inputs. It is set up to read from a FP-TC-120 for a dry bulb temperature and a FP-AIO-610 for a 0-10v signal from a humidity transmitter. When using two "FP Read" functions the program would read successfully from both modules and calculate for only one iterations. AFter that the the read for the analog input would give error 32812, the read from the thermocouple does not return any errors but the value is now zero. I then replaced the "FP Read" for the anaolog module to "FP Advise". With this set-up I get two succesful reads before the error message and the 0 thermocouple reading. I'm not sure what else could be the problem.
LabVIEW 2016 - Windows 7

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I have no experience with FieldPoint but I don't think you should be doing a close inside the while loop. Put the close outside so that is executed when the while loop finishes.
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Once again the forum saves me. I just hope that one day I will be able to give back all that I've taken. Its always the simplest things, thanks for your help.
LabVIEW 2016 - Windows 7

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Something else to take care of is the error handling. You split the error chain before the loop starts but only maintain the upper branch. The way the code is written, If an error occurs reading the second tag you'll never see it. The result is that the program will stop working and you won't know why.

Attached is a VI I wrote for merging two error streams.

Mike...

PS: Don't use NI's routine that claims to do the same thing. I will throw error data away on you...

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Hey,

I am programming a VI to calculate Wetbulb, Dew point and Mixing ratio. the ATMv12.vi is great.
Some of the letter i am not sure what they are.


I understand:

RH.....relative humidity
Tdp....Dew point temperature
Tw.....Wetbuld temperature

what is:

Y?
D?
Pa?
Pe?


thank you
Gio
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This thread is over two years old, so I am not sure if the original author will see it.

Message Edited by altenbach on 09-20-2007 02:03 PM

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Hi Gio,

Guess it pays to keep notes on things you've done before, had to dig back pretty far for this one :-).

Y - Gamma

D - Delta

Pa - Ambient Vapor Pressure

Pe - Saturated Vapor Pressure

Here is the link to the web site I used for a reference http://www.faqs.org/faqs/meteorology/temp-dewpoint/.  Hope that helps!!

 

LabVIEW 2016 - Windows 7

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