String tag alarm not executing

I am trying to alarm a STRING tag. The string will contain an error message, generated when a script creates an Exception error.

The Alarm is supposed to execute On Condition with the following binding on “Is Active”:

{Value}!= ""

The tag gets its value written to by an error handling script with a standard

system.tag.write(tagPath, msg)

But for some reason the alarm is not executing when a value is written to it. I can see the STRING value of the tag change in real time, but the alarm is not generated.

If I manually paste some text into the Tag value it seems to execute the alarm though. Is there some sort of scan issue at play here?

Have you looked at the tag diagnostics in both cases?

in stead of using {Value}!= “” can you use len({Value}) > 0?

I have tried this but it doesn’t seem to compile. Get an error in the Gateway console saying it failed to compile.

Where are the tag diagnostics? If it is in the Designer under Help->Diagnostics, i’m afraid i cant open that panel due to some other strange error.

Ah thanks.

Turns out the alarm was working, it just wasn’t showing up on my Alarm Status table which led me on a bit of a wild goose chase…
The use of a wildcard filter (ScriptErrors*) on the Display Path wasn’t working as expected.

Sorry for the wild goose chase, things always seem much easier to figure out after a short break.