Configure Attribute Logging in AWX Logger

BACnet PM takes advantage of alarm type inheritance (also possible in OPC UA and FrameWorX). For example, type OutOfRange is derived from BACnetAlarmType, which is derived from BaseConditionType, which is derived from BaseEventType.

Each type inherits all properties from all its parents and may add its own properties.

For example, type OutOfRange inherits property BACnetDeviceName from BACnetAlarmType.

The alarm type hierarchy and the properties can be observed when selecting fields in AlarmWorX Viewer.

Alarm Type Inheritance Hierarchy and Properties of BACnetAlarmTypeCon

Properties of OutOfRange Type

(Note that it also contains all properties inherited from the parent types. This shows just the added properties – specific to OutOfRange.)

AlarmWorX Logger is a Classic OPC AE client. OPC AE does not work with types and properties and does not support the concept of type inheritance and their hierarchy.  It defines Categories, which contain Attributes.

When logging alarms coming from FrameWorX, the alarm types are translated to Categories and the properties are translated to Attributes.

The inheritance hierarchy is lost because Classic OPC AE does not support this concept.

Each AE notification from BACnet (or FrameWorX in general) is of a certain type. Typically, the most concrete alarm types are sent; the parent classes are more abstract (usually  they serve as placeholders for the common properties).

When an out-of-range condition occurs, BACnet PM sends a notification of type OutOfRange. This notification is translated to an OPC AE event of the Category with the same name - OutOfRange.

Because of the lost inheritance hierarchy, it is necessary to set up AlarmWorX Logger to log the Attributes of the OutOfRange Category, NOT the Attributes of Category BACnetAlarmType!

The OutOfRange Category (or all other Categories derived from BACnetAlarmType) inherits the fields from BACnetAlarmType and adds some more.

Logging of the OutOfRange Category