For the purposes of this document, the terms and definitions given in the following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments and errata) applies.
link to arbitrary, live automation data, that is, data that represents currently valid information
- device data (such as temperature sensors),
- calculated data,
- status information (open/closed, moving),
- dynamically-changing system data (such as stock quotes),
- diagnostic data.
DataItemsthat represent continuously-variable physical quantities (e.g., length, temperature), in contrast to the digital representation of data in discrete items
Note 1to entry: Typical examples are the values provided by temperature sensors or pressure sensors. OPC UA defines a specific VariableTypeto identify an AnalogItem. Propertiesdescribe the possible ranges of AnalogItems.
DataItems that represent data that may take on only a certain number of possible values (e.g., OPENING, OPEN, CLOSING, CLOSED)
DataItemsthat represent continuously-variable physical quantities and where each individual data point consists of multiple values represented by an array (e.g., the spectral response of a digital filter)
units of measurement for AnalogItemsthat represent continuously-variable physical quantities (e.g., length, mass, time, temperature)
UA Unified Architecture