User Manual

Alarm management
Alarm management by notification class
9
CM110664en_07 153 | 353
9.6 Alarm management by notification class
With intrinsic reporting, the alarmable object itself assumes alarm identification
and state machine for alarm handling. However, the subsequent distribution of
alarm messages to alarm clients and the alarm management is no longer the
responsibility of the alarm source itself, but of a Notification Class object
assigned to the alarm source. The Notification Class object is both a D-MAP
function block and a standard BACnet object, which contains all the information
required for the distribution of alarms and system events within the system.
With algorithmic reporting, alarm detection and the state machine for alarm
handling normally are taken over by the Event Enrollment object. In this case,
alarm management also is set up in an alarm source via assigned Notification
Class object.
Each alarm-generating object is assigned one notification class [NotifCl] only,
but one notification class can be used by more than one alarm-generating
object. This makes it possible to create a Notification Class object for each
group of alarms (e.g., HVAC alarms, fire alarms etc.). Each alarm source in a
given alarm group is assigned to the [NotifCl] for that group.
There are global and local notification class objects:
● Global notification class: One set of max. 18 global notification class objects
per site. Global notification classes are replicated and thus exist on all
Desigo PX of a site in identical form.
● Local notification class: On Desigo PX, local notification classes can be
engineered, but are NOT replicated.
● Desigo room automation supports exclusively local notification classes.
The notification class function block [NotifCl] is the means by which
functionality is transferred from the BACnet standard into the CFC
environment.
This function block contains the instance number of the Notification Class (an
integer). which must be identical to the value entered in the subordinate alarm
sources. This makes it possible to create a unique reference.
The number must not be modified online.
There are 18 predefined global notification classes. The notification class is
identified with the two independent variables AlarmFunction and AlarmClass,
and referenced in the alarm source:
Intrinsic reporting
Algorithmic reporting
Notification Class
Interface definition
Notification class
number