Status Changes
Changes in system alarm states
The system responds only to changes in single states. Alarm conditions must be defined for changing the alarm states and operations corresponding to these changes. Objects of the Alarm type are defined by using the online system configurator - the D2000 CNF process.
The following table describes all the possible changes in system alarm states.
Alarm status change | Condition to change |
|---|---|
Normal -> Alarm | The condition to start the alarm must be met. The condition is represented by an object of BOOLEAN type. Change into the state Alarm is subject to the time filter. |
Alarm -> Acknowledged | The operator acknowledged the alarm. |
Alarm -> Normal | The condition of ending an alarm must be met. If the condition is not defined, the condition of starting an alarm has to finish. If the alarm is defined as an acknowledgement-required alarm, its status may not change from the state Alarm to the state Normal |
Acknowledged -> Normal | The condition of ending an alarm must be met. If the condition is not defined, the condition of starting an alarm must finish. |
Normal, Alarm, Acknowledged -> Blocked | The alarm is blocked by the operator. |
Blocked -> Normal, Alarm | The alarm is unblocked by the operator. New alarm status (Normal or Alarm) depends on which state the alarm was raised in. |
Alarm -> Unacknowledged | The condition of finishing an alarm is met - for an acknowledgement-required alarm. |
Unacknowledged -> Normal | The operator acknowledged the acknowledgement - required alarm. |
Unacknowledged -> Alarm | The condition of raising an alarm is met again - for an acknowledgement-required alarm. |