Hi, just a short question... I'm using Allen Bradley 1771-IR to monitor a PT100 RTD (3-wire RTD). According to the manual, if I remove the A terminal (excitation) the reading will go overrange. I found it different from what I've tried (it went underrange). They are true for terminal B & C (drift high and underrange) but not for terminal A. I just can't explain. I checked the theory behinds it but end up lost in the net with various diagrams of wheatstone bridge. Appreciate if somebody could answer.
TQ
TQ
