I am working on a conversion from an old RsView project where they have some tags that are alarmed, but they also have an "acknowledge" tag that only gets set back to False once the corresponding alarm has been acknowledged. I need some visuals to remain until the acknowledge has happened.
Does anyone know of an idea of how to accomplish something similar to this in ignition? I took a stab at it with expression tags and isAlarmActiveFiltered( but haven't been successful. My backup is to have the separate acknowledge step and tag done in the PLC but would prefer to do it without modifying the PLC and adding a bunch of new OPC tags if i can. Thanks!
One option would be to re-bind all of the "acknowledge" tags to the actual alarm status property of the parent tag. This would really only be feasible if those "acknowledge" tags are purely on the HMI side. If they're used in the code outside of display, you may need to write something like a gateway script to write values to the acknowledge tags based on the alarm status.
The downside of this is that its a bit messy and could get tedious if you have more than a couple alarms. There's several ways to do this I'm sure, but here would be one example:
alarm_status = system.alarm.getStatusForAlarm("alarm_name")
# Set the Acknowledge tag based on the alarm status
system.tag.write("[default]Acknowledge", 1 if alarm_status == "Active" else 0)
Thanks @jrusso, that gave me a good starting place. There are a couple hundred alarms i need to do this for but that really isn't a problem. system.alarm.queryStatus does seem to get me what i want if i query the specific tag and state "activeUnacked" What would be a good way to get this status bound to the acknowledge tag? I already have the alarm tag in a UDT so my first thought was an expression tag in the same UDT but i couldn't figure out how to query for the activeUnacked status with expressions. Would a runscript call in the expression tag be an option, or would i be better off with something like a gateway timer script that just set all the acknowledge tags on an interval be better?
A gateway script would probably be the best because you could more easily control its interval. Having 100s of tags calling the same runscript would be terribly inefficient.
If I'm understanding, you have the main alarm tag and acknowledge tag in the same UDT? If so, perhaps an alarm event script would be better. If you go into the UDT editor and scroll down to the scripting category, you can see the default event scripts.
From here you can write a 1 to the acknowledge tag on alarm active and a 0 on alarm acknowledged. This way you only would need to write them once and it would apply to every UDT.
This is EXACTLY what i needed, i didnt even know this existed, thank you! I just added a one liner to set the acknowledge flag on the alarm active event, and to clear it on the acknowledged event, works perfectly.
No problem! Like I said there are always 100 ways to do something in Ignition, and my original suggestion was a more generalized solution assuming a few separate tags. As soon as you said UDT a lightbulb went off in my head on how to do this waaaay simpler. Make sure to mark as solved!
