> For the complete documentation index, see [llms.txt](https://docs.novacura.com/flow-connect/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.novacura.com/flow-connect/working-with-connect/connect-to-systems/connectors/opc-ua.md). # OPC UA Use the OPC UA connector to interact with OPC UA servers directly from your workflows. It enables you to browse the server address space, read and write node values, and navigate object hierarchies, allowing seamless integration. Unlike the UI-based approach in Flow Classic, Flow Connect leverages Flow Script to programmatically browse nodes, read real-time process data, and write values to OPC UA server endpoints. ## Managing Connector : Add, Edit, or Delete Follow the [steps in the link](https://docs.novacura.com/flow-connect/working-with-connect/connect-to-systems/managing-connector) as a guideline for connector actions: Add, Edit, and Delete. ## Configuration values | Configuration | Description | | ----------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **Agent Group** | Specifies the agent group on which the connector will be executed. | | **Server Address** | The OPC UA server endpoint URL to connect to (e.g., `opc.tcp://hostname:4840`). | | **Use Security** | Determines whether to use a secure connection. When set to `Yes`, the Security Configuration options become available. Default: `Yes`. | | **Cache Metadata** | When set to `true`, caches the OPC UA server metadata locally to improve performance on `browseFolder` and `browseFromNode` operations. | | **Application Name** | The application name used to identify this client when connecting to the OPC UA server. Default: `applicationName`. | | **Application Uri** | *(Security enabled)* The unique URI identifying this application instance. Required when security is enabled. | | **Application Certificate Store Path** | *(Security enabled)* The file system path to the certificate store containing the application's own certificate. | | **Application Certificate Subject Name** | *(Security enabled)* The subject name of the application certificate used for secure communication. | | **Application Certificate Thumbprint** | *(Security enabled)* The thumbprint of the application certificate used for identification. | | **Trusted Peer Certificate Store Path** | *(Security enabled)* The file system path to the certificate store containing trusted peer certificates. | | **Trusted Issuer Certificate Store Path** | *(Security enabled)* The file system path to the certificate store containing trusted issuer (CA) certificates. | | **Rejected Certificate Store Path** | *(Security enabled)* The file system path where rejected certificates are stored for review. | | **Check Domain** | When set to `true`, validates that the server certificate's domain matches the server address. Default: `true`. | | **Additional Property String** | Optional string for passing additional configuration properties to the connector. The properties must be provided using the **exact XML format** described in the[ linked documentation.](https://docs.novacura.com/flow-connect/working-with-connect/connect-to-systems/connectors/opc-ua/additional-property-string) | ## Operations | Directory Operations | Description | | ------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [**browseFolder**](https://docs.novacura.com/flow-connect/reference/reference/flowscript/walkthrough/opc-ua-module#user-content-browsefolder) | Lists the items inside a standard OPC UA server folder (e.g., `ObjectsFolder`, `RootFolder`). Think of it like opening a folder on your computer to see what's inside. You can optionally filter what types of items to show and cache the results for faster repeated lookups. | | [**browseFromNode**](https://docs.novacura.com/flow-connect/reference/reference/flowscript/walkthrough/opc-ua-module#user-content-browsefromnode) | Lists the items connected to a specific node in the server. Similar to `browseFolder`, but instead of starting from a standard folder, you start from any known node and explore what's linked to it. | | [**readNodeValue**](https://docs.novacura.com/flow-connect/reference/reference/flowscript/walkthrough/opc-ua-module#readnodevalue) | Reads the current value of a data point on the server by its node ID. For example, reading a sensor temperature or a machine status. Returns the value along with timestamps and a status indicating whether the read was successful. | | [**writeNodeValue**](https://docs.novacura.com/flow-connect/reference/reference/flowscript/walkthrough/opc-ua-module#writenodevalue) | Updates the value of a data point on the server. For example, setting a target temperature or toggling a switch. You provide the node to write to, the new value, and the data type. Returns a status indicating whether the write was successful. | --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.novacura.com/flow-connect/working-with-connect/connect-to-systems/connectors/opc-ua.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.