OPC Method Trigger
OPC UA methods allow an OPC UA client to specifically execute functions or actions on an OPC UA server. A method can be called with input parameters and can optionally return results to the calling client.
With the OPC Method Trigger, the OPC Router provides an OPC UA method that can be called by external OPC UA clients. The method call serves as a trigger for a connection in the OPC Router. The parameters passed during the call can be further processed within the connection and forwarded to connected systems, plug-ins, or target components.
The trigger is particularly well-suited for scenarios in which an OPC UA client is not only supposed to read or write values, but also actively initiate a process in the OPC Router—for example, a data transfer, a posting, a recipe change, or the transmission of production information.
Dialog Overview
The screenshot shows the configuration dialog for the OPC Method Trigger. In the dialog, first select the internal OPC UA server and the target path in the address space. Then define the name, description, timeout, and the method’s input and output parameters.
Configuration
| Property | Description |
|---|---|
| Connection | Select the internal OPC UA server through which the method is accessible. |
| Server Path | Select the path where the method should be located. You can click the button with the three dots "..." to use the tag browser. |
| Name | Select a name for the method. |
| Description | Describe what your method does. |
| Timeout | The transfer is aborted after the set timeout (ms) has elapsed. |
Parameters
Input and Output Parameters
| Property | Description |
|---|---|
| Input | Define any number of input parameters, select the data types, and add a description if necessary. |
| Output | Define any number of output parameters, select the data types, and add a description if necessary. |
Procedure in the Dialog
- Select the desired internal OPC UA server connection.
- Use the tag browser to select the server path under which the method is to be made available in the address space.
- Assign a unique method name and add a description if necessary.
- Set the timeout and define the required input and output parameters.