Strain gauge circuit calibration with 741 op amps

[buffster88]

imdoin an experiment with a strain gauge sensor to measure mass. the 2 strain gauges are in a wheatstone bridge and the wheatstone bridge is connected to 3 741 op amps to amplify the signal. i need an output of cetain voltages for certain masses input.


My circuit is giving an output to high or too low for my requirement and when I get it right for 1 mass, it goes wrong for the next. Can anyone help? Need it urgently



Im using a pot to vary the resistance in the instrumentation amp circuit.

 

[dlgoff]

Welcome to PF.
It would be nice if you could provide a schematic of your circuit.