I can not measure strain gauge

I'm trying to work for strain gauge measurement with scc-sg04, sc2345 signal conditioner and ni-6223 DAQ card. Internal +2.5V supply I have used as excitation voltage. I want to get the data via Measurement & Automation explorer and I have created a task for strain measurement. I have selected the SCC1Mod1/ai0 channel for this purpose and adjusted task timing to Continuous mode. When I have pushed the Test button, Analog Input Test Panel is shown and observed strain value is -0.0021. This value do not changes while I pushing my finger to the load cell.
With +2.5V excitation voltage can I see the any changes for output (note that manufacturer recommends 10V excitation voltage).
Message Edited by immortal on 11-12-2007 02:11 AM
Message Edited by immortal on 11-12-2007 02:12 AM
Attachments:
fig.JPG ‏89 KB

Dear Hani,
Thank you for your reply firstly.
I connect external power as you give but there is some problems I have encountered. I connect cables of DC voltage supply to input of the load cell (DC supply is not running) but acquired data (there should be only noise ideally in this state) is fluctuating (See q3_1.jpg). After, I run DC supply and there is a sinusoidal wave in this phase (See q3_2.jpg). If I push my finger to load cell, DC value of this sinusoid changes only. So, I have a big problem with my external excitation supply .
The other problem I've encountered is Vex value of external excitation. I change Vex source to external and Vex=10V and my task is not working and gives an error as "requested value is not supported value for this property" (See q3_3.jpg). I couldn't understand why this error occurs.
Waiting your reply...
Attachments:
q3_3.JPG ‏76 KB
q3_1.JPG ‏31 KB
q3_2.JPG ‏30 KB

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