AlOPCUA Server is a process, that can be implemented on Windows or embedded in a target with Windows or Linux operating system.
Every server can connect to many plc runtimes and can publish all the symbols defined by the plc application.
It can be accessed from the server IP, with default port 48020.
The configuration of the OPCUA Server can be done with the simple configuration xml AlOPCUAServer.conf, here an example:
<?xml version="1.0"?> <opcuacfg> <instance name="PLC Local" protocol="gdb" params="127.0.0.1:5000" maxArrayElems="10" maxMatrixElems="5" /> <instance name="PLC Remote" protocol="gdb" params="10.0.0.91:5000" maxArrayElems="10" maxMatrixElems="5" /> </opcuacfg>
This simple configuration file specifies the server to connect to two plc runtimes, with protocol gdb, that is Axel's default.
The field name specifies the name of the root node for that plc in the OPCUA namespace.
The field params specifies protocol specific params: in this example the tcp IP and Port on which runtimes are listening for the gdb connections.
The last two fields maxArrayElems and maxMatrixElems are constraints about automatic array and matrix expansions feature:
under any array or matrix node, in the OPCUA namespace, the server will publish a node for each element of the array.
These two constraints limits the amount of elements that are automatically created.