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OPC UA Communication

Communication apps provide data from a source to the NOA bus, e.g. for telemetry in NOA Portal or building a HELIO HMI.

The OPC UA Communication establishes a connection to any OPC UA Server e.g. running on a controller.

  • KEB Controllers running Codesys Control on Windows (CE), e.g. the C6 Smart, can enable an additional OPC UA Server (this may require an additional license)
  • KEB provides a BETA of an OPC UA Server for Linux devices --> ask Systems Group
  • Third party controllers may also allow to enable an OPC UA Server, e.g. SIEMENS, Beckhoff, ...
  • An OPC UA Server may be simulated for testing, see (Capabilities HELIO and NOA (OPC UA) -- /NOA-Internal-Documentation/OPC-UA-Communication/Capabilities-HELIO-and-NOA-(OPC-UA)) for examples

Configure the parameters as below. Upon success the service

  • Shows the device's URL big on top, e.g. opc.tcp://10.120.104.51:4840
  • Starts reading the data tree immediately and shows the number of found nodes; this number keeps .... what? ...
  • Shows "Connected" in the green pill right next to it (this pill shows the connection status in general)
  • Parsing the tree may take a long time if the OPC UA server contains (too) much data
    • Use RootFolder to read only a part of this tree

⚠ Press the button "Test" to check if the OPC UA Server is available.
This will also fill out the server capabilities for "Authentication", "Message Security" and "Certificate Information"

overview

Prerequisites​

  • Configure the OPC UA Server properly e.g. for users and message security
    • Configuration depends on the OPC UA Server
  • An OPC UA Server usually publishes some information even without a PLC Program running
    • To access any PLC data make sure a program is running end exports the needed variables
  • To enable a Codesys OPC UA Server simply check the corresponding option, e.g. in COMBIVIS studio 6 > Symbol Configuration > Settings (make sure you have a license) image.png

Parameters​

  • Example URL opc.tcp://10.120.104.51:4840/OPCUA/Server
VariableData TypeDescription
Server AddressURLURL which gives access to the OPC UA server, typically consists of protocol opc.tcp://, device IP address 10.120.104.51 and OPC UA port 4840; may contain an additional path /OPCUA/Server
Root FolderOPC UA Node IdentifierStart scanning the OPC UA tree from this node; copy the node identifier from OPC UA server here, ns=4;s=AirConditioner_1 or i=31915 see screenshots below
Max DepthNumberNumber of levels to search from "Root Node" in the OPC UA data tree downwards; this is to limit the amount of data to fetch from the OPC UA server
Secure ConnectionAuthenticationLeave empty for anonymous access
User NameStringUsername as used by OPC UA server
PasswordStringPassword as used by OPC UA server
Output valuesread-only
Nodes CountIntegerShows the number of nodes parsed so far; status is "Browsing", done when "Connected"
Connection StatusStringReflects the detailed state of the connection, shown in the pill on top of the screen

Example Settings​

C6 Smart OPC UA Server Anonymous​

Anonymous connection; browse the OPC UA tree from the root up to 99 levels deep image.png

C6 Smart OPC UA Server Authenticated​

authentication to access (same as set in COMBIVIS Studio 6), starting from application node HELIO_ComTest, going 5 levels deep. Note the number of nodes on top changed image.png

Prosys OPC UA Simulation​

uses the non-default port 53530 and requires a path image.png

Python OPC UA Demo​

running on 10.120.104.41 image.png

Finding an OPC UA Node ID​

UaExpert: Copy node id as indicated in the screenshots (right click)
nodeID-01.pngnodeID-02.png

Troubleshooting​

  • OCP UA is a complex communication protocol, so not all features are supported
    • When you encounters such an issues, please report to support
    • See (Supported Features -- /NOA-Internal-Documentation/OPC-UA-Communication/Supported-Features)