Is there such thing as short term trending in Ignition? We are using PI as our standard process historian so Ignition is only used as HMI but it would be nice to have small trends along side values to provide context for the operators. Beside, I don't think we bought the historian module.
You can set up a transaction group to write specific values to a DB table on a 1 second interval, and then poll that table for short term data. You can set up your transaction group to delete records older than a set age if you don't need to keep the data for any long term trending. Transaction groups do require the SQL bridge module.
If you don't have the SQL Bridge module you can still script the equivalent of a transaction group in a gateway tag change event. You can include the dropping older records from this scripted transaction or let your database server handle it natively on the table you create.
I have a recorder() expression function in my Integration Toolkit module that will do short-term in-memory trends. You cannot use the Perspective PowerChart nor Vision EasyChart, though, as those charts do not accept custom datasets.
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Hi pturmel, can you elaborate a bit on how to do this? Is this "Integration Toolkit" something we have access to and what kind of chart do you use?
My Integration Toolkit module is an add-on module for Ignition that injects a bunch of useful expression functions and scripting functions. It does not provide any new components.
(Note, not available in Edge.)
The docs for the recorder() function are here:
https://www.automation-pros.com/toolkit/doc/datasets.html#recorder
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