Online edits of M340 program from Control Expert

[jerrybenny18]

Hi, I'm new to programming M340 controllers - my background is in Rockwell. I was wondering if there is an equivalent to "online edits" as we have in Rockwell - i.e making changes to the program without needing to stop the processor.

From my experience so far, if you want to do this in control expert, you have to be online to the PLC first, then make the changes and click "Build Changes" under the "Build" menu. Is this the only way to do it? This seems like if I made changes in an offline copy, that necessitates a PLC download even if it is only changing a few lines of logic? 

[dnordenberg1]

You don't need to be online while you edit and "Build" is the "online change". Just don't click Build while offline because that builds a new version of the program on your computer and it will now differ from the PLC when going online so it doesn't have the current program to compare the changes to any more. Some actions like changing settings and IO configuration can't be done with a online change, if you try to edit something of that Control Expert will warn you that you will need to build offline and then do a full download.

If you happen to hit build while offline and you done a lots of changes you don't want to lose, you can export your new program, upload a new copy from the PLC (if upload hasn't been disabled, it is normally allowed) and import your exported changes back over the uploaded project and then you have the current "compiled" project still preserved on your computer. You normally don't need to worry about how big the online changes are.

[Trinxs1 · Accepted solution]

JerryBenny18 online changes are made in the way you have described.  There is also a virtual connect mode where you can make changes (but only those that can be made online) to the project offline.  Reconnect as equal and then build online.  
In both cases however there are changes that require a rebuild all.  In this case you must stop the processor to undertake a full download.

Trial and error with the offline mode is the best way to detect which changes require a rebuild all.  In this case when a change is made open the PLC Build menu to see what options are available.  If only the "rebuild all" is available, then you must stop the PLC for a full download. 
In the virtual connect mode the build changes option should only be undertaken when online.  As soon as build or rebuild all is undertaken the projects are no longer equal.

[ciupol]

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@jerrybenny18 wrote:

 necessitates a PLC download even if it is only changing a few lines of logic? 

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I exactly know what you mean. In Rockwell when  you made a small change the online change is almost instantaneous. In Control Expert it takes much longer and looks and feels like a download. But that just how it is in Schneider. Still the concept is the same but the execution is completely different.