I recently purchased four tri-clamp rtd pt100 sensors and as I am wiring them up I have brought up two of the PIDs 3 of them are brand new and one is a year or two old. I now have 1 new and the old one powered up and all of the rtds are wired up to disconnects so I can interchange them and no matter which 1 I use in any vessel I keep getting a temperature reading of 1205 degrees. I used to just have a thermocouple on the old PID, and it worked just fine I know I have all of the wiring right. I have switched over the old PID to make sure it reads as an RTD, is there some mistake I'm making here I don't understand? Any help or clues would be very very much appreciated.