ČSN EN 62541-11

This part of IEC 62541 is part of the overall OPC Unified Architecture standard series and defines the infor-mation 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. This standard includes functionality to compute and return Aggregates like minimum, maximum, average etc.