Catching and logging recipe changes.

I have a machine that operator like to change stuff on then say no we didnt touch it. Well I want to start to log the portions of the recipe that changes and send it to another processor. Is it possible to only send the changes? I dont want to fill up our data collector if nothing changed.
We are using logix5000. Can someone give me an example of how to do this without having to send and or read the entire recipe? Would I have to do produced and consumed tags or messaging of some sort? I would reall appreciate an example on this.

Thanks alot.

What device does the operator use to make changes?

Some HMI packages support time-stamped logging. You may be able to do it there. If you must use the PLC, you should be able to create a UDT with a record for the time, the value that chagned, and the old value (or the new value, or both). Then create an array of these data types with enough positions to store as many changes as you need to record. You may already have logic that moves operator entries to display values, or to working registers. Yyou might be able to add branches to this existing logic to add entries to your log UDT.

If you don't already have this logic, you can use the DTR (data transition) instruction to detect changes. This is an input instruction that looks for a change in the Source element, and when it detects a difference, it passes logic and writes the value from the Source into the Destination.

Paul C.

can you give an example line and also could you tell me if we use time stamp logging on panelbuilder32 and with panelview1000.

Thanks again