Transmitter produces MA but DCS was showing IOP. DCS channel was healthy, checked by MA source, value was showing according MA. This transmitter connected to PLC, there It was healthy. New Transmitter connected to DCS Same Channel there it was healthy. so where is the problem in DCS or in Transmitter?
Check the wire continuity from field to DCS panel and check the DCS transmitter range because it’s processing value can be greater than its URV Value and lower than its LRV value.
you should check transmitter output by applying air pressure to the transmitter check if the output is changing or not if not changing means its output side has gone so the transmitter will show IOP there is no problem with DCS or channel… you should also check transmitter configuration