Colt Hero
Member
Is it possible to dynamically change Tag Names (in real-time) on these PLCs? I'm guessing the answer is "NO", right? Just externally, then re-save, correct?
I've got multiple applications that are all pretty similar that are currently separate apps. They all differ here and there, but not substantially. I'd like to make them ONE application, fully configurable at start-up, but the "gotcha" is - the Tags to the Historian have to be unique. The Historians are running on separate Servers, but in one case, two of these apps write to the same Historian, so that eliminates the possibility of using (somewhat) "generic" tagnames.
So the workaround would be to have a routine that just reads and writes from/to the respective data sets based on the System selected at Startup, but it would be much cleaner if the tag names themselves could be modified at Start-Up after the System Selection is made.
Someone's probably gonna chime in and say, "You want a self-modifying program". Yeah - but only because these PLCs are so "name" driven, instead of memory-location driven. Or ... maybe it's because of the way their data exchange works (OPC). If this was a "conventionally-designed" system, it would just be data buffers with implied data positions. You could name the cells of the buffer anything you wanted in your local program.
Could the data be sent another way ... say ... in a block? The Historian is "PI", BTW.
I've got multiple applications that are all pretty similar that are currently separate apps. They all differ here and there, but not substantially. I'd like to make them ONE application, fully configurable at start-up, but the "gotcha" is - the Tags to the Historian have to be unique. The Historians are running on separate Servers, but in one case, two of these apps write to the same Historian, so that eliminates the possibility of using (somewhat) "generic" tagnames.
So the workaround would be to have a routine that just reads and writes from/to the respective data sets based on the System selected at Startup, but it would be much cleaner if the tag names themselves could be modified at Start-Up after the System Selection is made.
Someone's probably gonna chime in and say, "You want a self-modifying program". Yeah - but only because these PLCs are so "name" driven, instead of memory-location driven. Or ... maybe it's because of the way their data exchange works (OPC). If this was a "conventionally-designed" system, it would just be data buffers with implied data positions. You could name the cells of the buffer anything you wanted in your local program.
Could the data be sent another way ... say ... in a block? The Historian is "PI", BTW.
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