I have auma positioner without screen. For 2 years it worked good at analogue signal.if the scada setpoint 0 the auma operate untill give 4 mA feedback and stopped
But sometimes make trip but we handle it untill the feedback 4 mA
This auma working open and close a telescopic valve .to avoid this trip we removed 2 fixed plates .and working fine but the auma stop at 5.7 mA and not completing the close .but if i turn the auma to local and close it .the auma close good and feed back 4 mA
The question is.why when i use analogue signal from scada. The auma not completing the close and stopped at 5.7 mA
I tried to adjust the 4 -20 .but the same result. Thank you guys

 

> open and close a telescopic valve .to avoid this trip we removed 2 fixed plates .and working fine but the auma stop at 5.7 mA

I have no idea what removing plates means. Remove what plates? sketch or photo of what the plates are?

What does it means to "avoid this trip". What was happening when the plates were in place?