OPC-UA¶

Characteristics - OPC-UA¶

OPC (Open Platform Communications) enables access to machines, devices and other systems in a standardized way. To learn more about the standard visit the OPC-UA website.

Information Model Requirements

The following Node Types can be used to model data structures:
- Variables with a Simple Data Type.
- Variables with a Custom Data Type.

Configuration - OPC-UA Client¶

Select OPC UA Client as Channel Type.
Click the Configure button.

Make sure the root model node is selected to configure the OPC-UA Client
Enter an Application name
Input the TcpConfiguration

Enter an IP address
Enter the Port
Define an Endpoint
Set a Request timeout

Configure the defaultSubscriptionAttribute

Define a Publishing interval and select the Unit

Configure monitoringParameters

Set a Sampling interval and the Unit
Enter a Queue size
Enable Discard oldest depending on the use case

Enable Subscription Groups depending on the use case
Input the Group name
Define a Publishing interval and select the Unit
Set a Sampling interval and the Unit
Enter a Queue size
Enable Discard oldest depending on the use case

Select the complex variable node.
Enable the Node configuration

OPCUAClientComplexVariableNodeEnableConfig

Assign OPC-UA data block variables to corresponding variables in the Information Model by selecting the variable in the tree
Assign data block

Enable the Nodes configuration checkbox
Enter the Node Id

Description of configuration properties:

Property	Description	Example
IP Address	Client IP	`127.0.0.1`
Port	Client port	`4840`
Endpoint path	Service name at the server endpoint	`demo`
Publishing interval	Interval in which Notification Messages are sent	`1`
Sampling interval	Sampling interval of monitored items	`10`
Queue size	Max number of messages stored in the publish queue	`1`
Node id	Id of the item	`s='DB_Processing_Module'`

Configuration - OPC-UA Server¶

Select OPC UA Server as Channel Type.
Click the Configure button.

Make sure the root model node is selected to configure the OPC-UA Server
Enter an application Name
Configure TCP

Enter an Ip Address
Enter the Port
Define an Endpoint

Configure the NameSpace

Provide a Root node name

Configure the variable sampling interval

Set the Initial delay in milliseconds
Input the Sampling rate in milliseconds

Description of configuration properties:

Property	Description	Example
IP Address	Server IP	`127.0.0.1`
Port	Server port	`4840`
Endpoint path	Service name at the server endpoint	`demo`
Root node name	The name of the top-level node in the OPC UA server’s address space	`PLC`
Initial delay	The time the OPC UA client/server should wait before attempting to connect to the OPC UA server	`10`
Sampling rate	The rate at which the OPC UA client/server requests data from the OPC UA server	`1`