I am evaluating the Alarm module to send SMS alarms.
I have succeeded using a PLC bit to trigger the alarm and send message so that construct works.
Next I needed to use Kepware to connect to iFix database using OPC-DA and that appears to be work fine.
I can see the values I expect in the Designer tag browser so I know its being seen.
So I want the alarm setpoint to look at a string being returned from am AA tag in the iFix Database and if it says anything other than OK, I want it to set the alarm and send that value.
The Alarm mode settings are
Equal
{[path]Tag} != ‘OK’
Also Tried {[path]Tag.Value} != ‘OK’
Tag Diagnostics see no syntax error in my string. so why is this not firing an SMS message?
Assuming that the tag provider is included in that tag path, the expression should be working fine to return 0 when the tag in the expression has the value ‘OK’. It will match this value to the value of the tag on which the alarm is configured, and evaluate the alarm state.
Using the Alarm Status Table, are you able to confirm that the alarm goes active when the tag value is 0?
Turns out that I needed to use “ON CONDITION” and not “EQUALS”.
I was equating Strings and equals wouldn’t work.
Now, if I used an IF statement as the query it would have worked.
Also found there is a bug in 7.9.1 that the properties of a STRING tag are not shown in the browser like they are for every other type. Explanation was that it used to be that you couldn’t alarm on a string type, but that ability was recently added, but adding the ability to view all those properties was inadvertently left out. It’ll be fixed in the future (after 7.9.1 obvi )