I’m working on a PLC stress test with Ignition, we’re testing out how well we can do historian on two PLC’s with varying amounts of resources allocated to Ignition. I have two PLCs, an Allen Bradley Micrologix and a Click PLC, both with 100 int tags each that I want to make a history for. For the Allen Bradley the consecutive registers for 0-99 under N7. For the Click I am not sure yet.
What is the easiest most maintainable way to create these tags (maintainable being if I want to change something for all 100 tags, I only change it one place)? My memory says this would be a time for me to create two UDT’s (on for each PLC) with one parameter a number from 0 to 99 that will correspond to the correct tag path. Inside the UDT the historian will be checked off as well.
- Is this a reasonable way to do this?
- What is the method for creating say 100 instances of the UDT with the parameter being 0 for the first, 1 for the next, etc? I cannot recall what feature was called or how to access it.
- I’ve seen lots of posts about configuring tags with scripts seems - would that be a better way of doing this? What would that methodology look like and were would that script be called? As a oneshot, inside a gateway event, any pitfalls?
The UDT instance creation wizard is what you are looking for.
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Somehow I knew it’d be you lol. Thanks @pturmel
Tangentially related - is there a way to view the highlighted text? I just want to make sure that my parametrized path is correct. I can’t seem to see the whole text.
Hi @bkarabinchak.psi,
It should appear in the OPCItemPath of the tag instance in the Tag Browser.
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Thanks for the answers.
Last question. We have these PLC’s connected via a Wi-Fi HaLow, their on one side of the office and my Wi-Fi Halow is on the other (just found out this is what we are actually stress testing here). I want to monitor all 100 for drops in connection/quality. I have all my tags AllenBradley tags in a folder like so -
And I am trying to create a gateway tag change event to write to the database in the event of bad tag quality. Right now the way I can see it working doing the whole folder
and having a conditional that if the tag quality is NOT good, then run some script, and feed it the tag path so I know which one was problematic (not that it really matters but its good to have the data). What is available to me inside the gateway tag change script? Normally Ignition tells you what function is being called and what you parameters you have access too but not here 
. How can I check that the tag quality is bad (or at least NOT good) and the tag path that triggered it?
This can be found: Gateway Event Scripts - Ignition User Manual 8.1 - Ignition Documentation under the heading Tag Change Objects.
You can use: newValue.getQuality()
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