Signal Conditioning

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when using MAX i got good readings, but when i use the labview the readings aren't ok

i am trying to install DAQ system for monitoring
and datalogging for 70 variables ,
the system consist of
-(4)scxi1100 32 channels -multiplexer- amplifier
- PCI6023 card
- scxi 1001 chassis with 12 slots
- (4) scxi-1308 chnnel therminal block
- labviwe base package for window

when i configure the variables using MAX i got good results, but the readings aren't ok when i use the labview program because they are changing up & down around the actal value .. i hope someone can help me ..
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Hi,
normally when your hardware is working in MAX correct than it should also working in LabVIEW. What for a LabVIEW Version are you using? How to present the data, do you use a graph or a numeric indicator?

Rebecca F.
Applications Engineer
National Instruments
SRQ 198368
National Instruments Germany
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thanks Rebecca for your response .. i'm using version 6.02 , i present data both with graph & numaric indicators .. i feel that the probem is with the labview .. i'll try to send the file if its possible to advice me about it ... thanks in advance ..

o. shaebi
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Hi again Rebecca ,

the attachment file is the labview program which i used , i hope this will be useful to advice me to fix the problem

thanks in advance

o. shaebi
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Hi,

sorry for the late answer, is the problem still up to date?
I tried to open your VI, but Labview misses the "My single scan processing.VI". Can you please send it to me?
I also need informations about the accuracy of the measurement( how strong does it change up&down?), f.e. 5V +-1V

Regards

Peter Weber
NI Germany
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Hi peter , thanks for your replay
yes the problem still up to date , i don't know how can i send the file to you? , my email is:
iron_m2000@yahoo.com

the accuracy is like the following example:
the tempreture of the position x is changing from 27 degree to 18 degree while the actual value is around 21

thanks again ,
best wishes

o. shaebi
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Hi,

can you please post the missing VI here in the forum, so that other visitors of this article can reproduce the problem?!

You measure the temperature as Voltage, rigth? What is the input range(f.e. 0...5V) and the failure of this signal? I need this informations in order to calculate the amount of toggeling bits.

regards,

Peter Weber
NI Germany
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Hi , thanks for the response
i tried to sent the file but all the time i recieve error.
i hope i'll success today.
i'll attach again the main file with the missing one.

i measure the temp. as current (0-5mA)
1mA give us 20 degree in scale of 1000 degree>

thanks again
best wishes
o. shaebi
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Message 8 of 10
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Hi,

I have just tested your VI with my PCI 6024E-Card.
The programm seems to run fine, but I'm not sure what you intend to do with it.
Can you explain the function of the sequence, you use in the VI?
At the moment, your VI aquires one value every 5 seconds, is that your aim?

Regards

Peter Weber
NI Germany
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Message 9 of 10
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hi peter ,
the program run fine with me too , the problem is: all the indicators are placed to measure variables like tempreture,level, pressure, flowrat , .. etc .
also the data is wanted to be saved to file .
i started to aquire 8 variables to be sure that every thing is fine, but i noticed that the reading is changing up & down , although when i tested the signals by MAX , the are fine.
my aim is to aquire the signals every 1 second , i tried to increase the time to avoid the changing , but without any use.

i hope i could undrestood your questions , also i hope my answeres are clear to you

thanks again
best wishes

o. shaebi
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