Hi Michael, If the excitation and reference are the same voltage source, then you should not see the drift of the source within the measurement. This assumes that the components do not drift. We often will use a large ESD bag or isolation box to limit the air currents that surround the components. We have seen significant drift due to air currents from fans, and adjacent equipment. There will be some self-heating of the components in the wiring, strain gauge and any resistors connected. I created a bridge using low drift, 499 ohm precision resistors excited from the internal reference connected to J8 and saw the same output as I did when I had shorted inputs biased to mid-supply. As the output was close to zero from the bridge, I would expect the results to be similar. I will attempt the experiment again using a different resistor in one of the legs to increase the output. The whole EVM was placed into a large ESD bag to isolate from external air currents. Best regards, Bob B
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