IEC 62541-11-2020 OPC unified architecture – Part 11: Historical Access

IEC 62541-11-2020 OPC unified architecture – Part 11: Historical Access. This part of IEC 62541 is part of the OPC Unified Architecture standard series and defines the information model associated with Historical Access (HA). It particularly includes additional and complementary descriptions of the NodeClasses and Attributes needed for Historical Access, additional standard Properties, and other information and behaviour. The complete Address Space Model including all NodeClasses and Attributes is specified in IEC 62541-3. The predefined Information Model is defined in IEC 62541-5. The Services to detect and access historical data and events, and description of the ExtensibleParameter types are specified in IEC 62541-4. This document includes functionality to compute and return Aggregates like minimum, maximum, average etc. The Information Model and the concrete working of Aggregates are defined in IEC 62541-13. 2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC TR 62541-1, OPC Unified Architecture – Part 1: Overview and Concepts IEC 62541-3, OPC Unified Architecture – Part 3: Address Space Model IEC 62541-4, OPC Unified Architecture – Part 4: Services IEC 6254 1-5, OPC Unified Architecture – Part 5: Information Model IEC 62541-8, OPC Unified Architecture – Part 8: Data Access IEC 62541-13, OPC Unified Architecture – Part 13: Aggregates 3 Terms, definitions, and abbreviated terms 3.1 Terms and definitions For the purposes of this document, the terms and definitions given in IEC TR 62541-1, IEC 62541-3, IEC 62541-4, and IEC 62541-13 as well as the following apply. ISO and 1EC maintain terminological databases for use in standardization at the following addresses: ●IEC Electropedia: available at htp://ww .electropedia.org/ ●ISO Online browsing platform: available at htpt://ww.iso.org/obp 3.1.1 annotation metadata associated with an item at a given instance in time Note 1 to entry: An Annotation is metadata that is associated with an item at a given instance in time. 3.1.2  BoundingValues values associated with the starting and ending time Note 1 to entry: BoundingValues are the values that are associated with the starting and ending time of a ProcessingInterval specified when reading from the historian. BoundingValues may be required by Clients to determine the starting and ending values when requesting raw data over a time range. If a...