Orphan alarms

I’m currently having an issue with analogue alarms. I have a point with a high alarm of 100 (inclusive) to infinity; Ack Mode is Manual; Send Clear is True; Alert Deadband is set to 5. What I expected to happen is an alarm will be raised when the value reaches 100, and will not clear until the value drops to 95. The following sequence of events occurs:

  1. The value increases to >100 and an alarm comes up.

  2. The value drops to 99 - because of the deadband no clear is sent.

  3. The value increases again to >100. A second alarm is raised.

  4. No clear is sent even when the value drops below the deadband.

If the value is ‘trembling’ around the alarm level, steps 2 and 3 can be repeated many times.

The result of all this is that many orphan alarms appear in the alarm list, with no way of clearing them. Any ideas?


Yes, this does seem to be a problem on our end. It’ll be fixed in 4.2.