Namespaces are used by OPC UA to create unique identifiers across different naming authorities. The Attributes NodeId and BrowseName are identifiers. A Node in the UA AddressSpace is unambiguously identified using a NodeId. Unlike NodeIds, the BrowseName cannot be used to unambiguously identify a Node. Different Nodes may have the same BrowseName. They are used to build a browse path between two Nodes or to define a standard Property.
Servers may often choose to use the same namespace for the NodeId and the BrowseName. However, if they want to provide a standard Property, its BrowseName shall have the namespace of the standards body although the namespace of the NodeId reflects something else, for example the EngineeringUnits Property. All NodeIds of Nodes not defined in this document shall not use the standard namespaces.
Table 11 provides a list of mandatory and optional namespaces used in an OPC 40564-2 OPC UA Server OPC UA Server.
Table 11 – Namespaces used in an OPC 40564-2 Server
|
NamespaceURI |
Description |
Use |
|
Namespace for NodeIds and BrowseNames defined in the OPC UA specification. This namespace shall have namespace index 0. |
Mandatory |
|
|
Local Server URI |
Namespace for nodes defined in the local server. This namespace shall have namespace index 1. |
Mandatory |
|
Namespace for NodeIds and BrowseNames defined in OPC 10000-100. The namespace index is Server specific. |
Mandatory |
|
|
Namespace for NodeIds and BrowseNames defined in OPC 40001-1. The namespace index is Server specific. |
Mandatory |
|
|
Namespace for NodeIds and BrowseNames defined in OPC 40560. The namespace index is Server specific. |
Mandatory |
|
|
http://opcfoundation.org/UA/Mining/MineralProcessing/General/ |
Namespace for NodeIds and BrowseNames defined in OPC 40564-1. The namespace index is Server specific. |
Mandatory |
|
http://opcfoundation.org/UA/Mining/MineralProcessing/RockCrusher/ |
Namespace for NodeIds and BrowseNames defined in this document. The namespace index is Server specific. |
Mandatory |
|
Vendor specific types |
A Server may provide vendor-specific types like types derived from ObjectTypes defined in this document in a vendor-specific namespace. |
Optional |
|
Vendor specific instances |
A Server provides vendor-specific instances of the standard types or vendor-specific instances of vendor-specific types in a vendor-specific namespace. It is recommended to separate vendor specific types and vendor specific instances into two or more namespaces. |
Mandatory |
Table 12 provides a list of namespaces and their indices used for BrowseNames in this document. The default namespace of this document is not listed since all BrowseNames without prefix use this default namespace.
Table 12 – Namespaces used in this document
|
NamespaceURI |
Namespace Index |
Example |
|
0 |
0:EngineeringUnits |
|
|
2 |
2:DeviceRevision |
|
|
3 |
3:MachineComponentsType |
|
|
4 |
4:MiningEquipmentType |
|
|
http://opcfoundation.org/UA/Mining/MineralProcessing/General/ |
5 |
|
(normative)OPC 40564-2 Namespace and mappings
Namespace and identifiers for OPC 40564-2 Information Model
This appendix defines the numeric identifiers for all of the numeric NodeIds defined in this document. The identifiers are specified in a CSV file with the following syntax:
<SymbolName>, <Identifier>, <NodeClass>
Where the SymbolName is either the BrowseName of a Type Node or the BrowsePath for an Instance Node that appears in the specification and the Identifier is the numeric value for the NodeId.
The BrowsePath for an Instance Node is constructed by appending the BrowseName of the instance Node to the BrowseName for the containing instance or type. An underscore character is used to separate each BrowseName in the path. Let’s take for example, the MiningEquipmentType ObjectType Node which has the add-in Identification object. The Name for the Identification InstanceDeclaration within the MiningEquipmentType declaration is: MiningEquipmentType_Identification.
The NamespaceUri for all NodeIds defined here:
The CSV released with this version of the specification can be found here:
NOTE The latest CSV that is compatible with this version of the specification can be found here:
A computer processible version of the complete Information Model defined in this document is also provided. It follows the XML Information Model schema syntax defined in OPC 10000-6.
The Information Model Schema for this version of the specification (including any revisions, amendments or errata) can be found here:
NOTE The latest Information Model schema that is compatible with this version of the document can be found here:
Annex B(informative)Bibliography
[1] DARLING, P., 2011. SME Mining Engineering Handbook [online]. 3rd ed.
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