Notifications (email or text file) are sent when an alarm is enabled by the shunt variable
The Alarm object has 6 possible states that it can take
The notification is triggered by transitioning to any of these states as selected in the "Notify on transition to" portion of the notification configuration
This means that if you wish to receive a notification on transition to the Normal state, you can check the Normal box. However, this means that not only are notified when the alarm transitions from Alarm to Normal, but from Disabled to Normal or Fault to Normal. Some of the scenarios may be undesirable.
There are two ways an alarm can go to Normal:
- Alarm to normal
- Disable to normal
In the Email notification main filter, you can choose to not get a notification from disarm but you might want to get a email about normal since you want to get a email when an alarm goes to normal.
To accomplish this you need to add another filter called "Previous alarm state." (This filter does not work in releases prior to 1.3 SP1.)
To add the filter Previous Alarm State:
- Click on the green +
Check the boxes you want:
- Make sure Disable is not checked
This means that when the previous state was disabled (shunted), a notification will not be sent.
Example1: This object will always trigger a notification on Alarm. The notification will be triggered regardless of Previous State. If the Alarm is Disabled by a shunt, then enabled, but the Monitored Variable is still out of Range, a notification will be sent.
Example2: This object will only trigger a notification on the Transitions from Alarm to Reset, Alarm to Normal, Acknowledged to Reset or Acknowledged to Normal. This might be desirable for a user that wished to know when an object in Alarm returns to normal operation, but not know when an alarm goes from Disabled to normal operation.