LabView 7.1, FieldPoint FP-AI-100, VI shows different values than NI-MAX

LabView 7.1, FieldPoint FP-AI-100, VI shows different values than NI-MAX

Post by Andre_Sall » Thu, 26 Jul 2007 17:10:05


Hello,
I have a guess:
the difference between the channels that work and that don is in the scalling. The ones that work fine use integer values for the scaling, those who don have floating point values in their scaling. It must have something to do with the decimal point.
I made some calculations that could prove this:
For example the channel "Versorgungsdruck": You can calculate the raw data backwards from the value shown in MAX:
x=(y+6.25)/1562.5=(6.900034+6.25)/1562.5=0,00841602176
Now we asume that because of an error, in LabVIEW the values behind the decimal point are ignored by LabVIEW, and we calculate the Y-Value again:
y=(1262*x)-6=(1562*0,00841602176)-6=7,14582598912
Here you go! Exactly what you see in LabVIEW.
So the value is calculated by LabVIEW in a different way then in MAX, because of LabVIEW ignoring all values BEHIND the decimal point, which can only mean that the decimal point settings don match.
You are using "Use localized decimalpoint" in LabVIEW (Can be seen on the frontpanel, as the decimal point is a comma instead of a dot). Try switching this option off (Menu: Tools->Options->Front Panel->Use localized decimal point)
remember that you have to restart LabVIEW, so that the cange takes effect.
Hope this helps!
 
Andr?  
Message Edited by Andre_Saller on 07-25-2007 03:06 AMMessage Edited by Andre_Saller on 07-25-2007 03:07 AM