Dynamic strain measurement

Sir,
My experiment involves the measurement of strain on the specimen on the application of torque.
I'm using SC-2043SG for the quarter bridge ,with an internal excitation of 4.13V.
I'm using PCI-MIO-16E4 DAQ device.
The DAQ Driver used is NI-488.2 2.30
Measurement and automation explorer version is 3.1.1
The problem is that when i apply 1.5 Nm and 2Nm torque, both are showing the same strain, 243 microstrain.
Whereas in the digital multimeter they show .7mV and .9mV respectively.
The strain is supposed to vary , which is not happening for every 0.5Nm. The multimeter is showing a
variation of .1mV for every 0.5Nm increase in torque. But this is not being shown in the strain output. Only
when it reaches 3Nm it shows 486 Nm. But this remains the same even for 4Nm.
external signal conditioning is also not helping.
The automation explorer test run is always showing the same value about some -2.Its not at all changing inspite of the different toques applied
thanking u

Hi Neil,
I' ve used the traditional NI DAq version 7.4 0f0.
I had first connected to active strain gauge to a bridge completion circuit using 3 other SGs to form a full bridge. And then i have tried the method specifeid in the SC-2043-SG manual by following these steps.
SW1 for power supply
W1 and W3 For excitation
W8 for excitation
W2 for channel 0 input
W7 for HB for channel 0
placed the 120 Ohm bridge completion resistor in the socket R52
connected the lead wires from the active strain gauge to the +EX0 and +CH0 screw terminals.
I have connected nothing additional to what i have specified here.
I'm getting the same kind of output for both methods.
The outputs are fluctuating between values.
I don't know what is wrong in my configuration.Plz help.
i'm attaching the results of the torques applied in the order 1Nm,1.5Nm,2Nm,2.5Nm,3Nm,2.5Nm,3Nm,3.5Nm,4Nm
Thanks a lot
Attachments:
Document.rtf ‏873 KB

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Sir,
My experiment involves the measurement of strain on the specimen on the application of torque.
I'm using SC-2043SG for the quarter bridge ,with an internal excitation of 4.13V.
The problem is that when i apply 1.5 Nm and 2Nm torque, both are showing the same strain, 243 microstrain.
Whereas in the digital multimeter they show .7mV and .9mV respectively.
The strain is supposed to vary , which is not happening for every 0.5Nm. The multimeter is showing a
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external signal conditioning is also not helping.

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