moosemoose
Member
Just to get the conversation started...
I have a Modbus card installed in the plc rack, I have a list of Global Labels that are all signed word DATA types. I am working in ladder logic attempting to use the MOV instruction to copy from one label to another label which are tied to data registers within the Modbus card. It seems that I am observing an inconsistent behavior; I can use the MOV instruction at one point without issue, then just a few rungs down the program it errors out. See the images for detail. Any thoughts would be greatly appreciated! Thanks!!
Images:
- the first should be a rung of logic works fine,
- the second is a very similar rung with different labels that error out,
- the third and fourth are the label definitions, and
- the fifth is the Modbus card configuration parameters.
I have a Modbus card installed in the plc rack, I have a list of Global Labels that are all signed word DATA types. I am working in ladder logic attempting to use the MOV instruction to copy from one label to another label which are tied to data registers within the Modbus card. It seems that I am observing an inconsistent behavior; I can use the MOV instruction at one point without issue, then just a few rungs down the program it errors out. See the images for detail. Any thoughts would be greatly appreciated! Thanks!!
Images:
- the first should be a rung of logic works fine,
- the second is a very similar rung with different labels that error out,
- the third and fourth are the label definitions, and
- the fifth is the Modbus card configuration parameters.