Emerson Exchange 365

In my experience, this behavior is most commonly an issue with your transmitter or your loop calibrator. The Series 2 AI card has an accuracy of 0.1% of span.

If you are sure your 4-20mA source is calibrated to at least the accuracy of the AI card (meaning your 4-20mA from the field is definitely 4-20mA +/- 0.1%, etc...), you can adjust the XD_SCALE of the AI block to match the span of your field signal.

I would recommend mapping multiple points between 4 and 20 mA, in case there is a nonlinear response. If that is the case, you may need to have a Signal Characterizer block downstream to provide a lookup table to adjust for that nonlinearity.