This specification defines a standard Object that can be used to collect information, like diagnostic information, in a standard manner. This Object can collect information defined in base specifications, companion specifications or even generated by an application that is loaded into a device or Server. This allows a standard Client to access the information and provide a standard manner for user access to this information.

The LogObject returns LogRecords via the GetRecords Method.

The LogRecords when they are generated, can also be sent as Events (see 6).

The LogObject does not define how the information is stored, only how it can be collected and how it can be accessed. This allows a vendor to choose the most appropriate storage for the information.

The LogObject is illustrated in Figure 1.

Figure 1 – LogObject usage illustration

Figure 1 illustrates both a predefined LogObject (ServerLog) and application defined LogObject (MyApplicationLog). The green boxes are defined in this specification, the blue boxes are defined in OPC 10000-5 or OPC 10000-22, the orange boxes are defined in the OPC UA FX specifications and the grey boxes are not defined in any specification.

Annex A and Annex B provide additional examples of LogObjects and possible Client uses and Server implementations.

This specification defines ObjectTypes, EventTypes, ConditionClass and instances (see Figure 2). Not all of the illustrated types/instances are required for an implementation and are covered by separate ConformanceUnits and Facets.

Figure 2 – Overview of LogObject Information Model