I have a project where I am using some RTD temperature sensors. These sensors can have from 2 to 4 connections depending on the sensor selected. The analog input port on the PLC module has four connections and instructions how to connect the type of sensor you are using (2, 3, or 4-wire)
I was doing fine assigning my digital inputs and digital outputs to specific hardware connections but when I got to the RTD sensors the sensor complained that I was trying to connect one analog input function type to four analog input circuits. How should I be going about this. My VAR has been as helpful as they can be but they are climbing the learning curve with me on SWE.
First I select the relevant circuits that make up analog input 2, then I click the Associate IO button on the tool bar...
That brings up the Inputs/outputs selection box. I select the function and analog input from the tree and click the Select button...
Then I get the following four message boxes one after the other...
An finally I am returned to the PLC manager showing that only the first circuit in my selection is associated with the desired function.
What am I doing wrong?
Looks like the inputs have only one circuit each, where you need two.
To do what you need, they should have two entries under "Terminal Number", separated by a comma.
ie "X11-AI2 M+,X11-AI2 M-"