User Manual

Alarm management
Alarm functions
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● Acknowledgement: Confirmation of an incoming alarm
● Reset: Confirmation that an alarm is no longer present
This type of interaction can be carried out locally or with clients, via the network.
Standard pattern
There are three standard categories of alarm, or alarm functions, reflecting the type of acknowledgement
required:
● Simple alarm
● Basic alarm
● Extended alarm
Each alarm source is assigned (via a Notification Class, see further below) to one alarm function only. No
further distinction is made at this stage between OFFNORMAL and FAULT alarms.
Simple alarm
Neither incoming alarms (disturbance appears) nor disappearing alarms (disturbance disappears) require
acknowledgement.
Basic alarm
Acknowledgment is required for incoming alarms only, but not for alarms that have been cleared (that is,
acknowledgement required but not reset).
Extended alarm
Locking alarm with acknowledgement of incoming alarms (disturbance appears) and cleared alarms
(disturbance disappears). Alarms in this category require both acknowledgement and reset.
While testing the system, it may not be possible to reset an alarm. The reason is that an Extended Alarm is
not reset until it has been acknowledged, and the time delay has expired.
The alarm remains locked until the fault has disappeared and has been acknowledged and a reset has
been carried out, e.g.: