Integrate Roboflow with OPC UA

Roboflow released a guide for integrating its computer vision workflows with OPC UA servers, enabling detection data to be written as live tags accessible to PLCs, SCADA, and dashboards. The process requires a Roboflow Enterprise plan and involves configuring an inference server with enterprise blocks, setting up destination tags on an OPC UA server, and using a Property Definition block to convert predictions into single values for each tag. The integration allows vision detections to function alongside other plant sensors in industrial automation systems.

This guide shows how to push Roboflow Workflow https://roboflow.com/workflows/build?ref=blog.roboflow.com detections to an OPC UA https://en.wikipedia.org/wiki/OPC Unified Architecture?ref=blog.roboflow.com server, making them available as live tags to dashboards, PLCs https://blog.roboflow.com/programmable-logic-controller/ , and SCADA https://blog.roboflow.com/what-is-scada/ platforms alongside any other plant sensor. Prerequisites Roboflow Enterprise plan — the OPC UA Writer Sink is enterprise-only Docker Desktop An existing OPC UA server — Ignition, Kepware, or any standards-compliant server. No server yet? Roboflow's edge devices ship with a built-in OPC UA server you can use for testing, covered in Step 2. Step 1: Start the inference server with enterprise blocks enabled Enterprise blocks including the OPC UA Writer Sink aren’t loaded by default. Without this step, the block shows “Server Configuration Required” in the workflow editor and never runs. 1. Create and activate a virtual environment python -m venv venv source venv/bin/activate 2. Install inference pulls enterprise blocks + dependencies pip install inference 3. Create .env with the critical flag echo "LOAD ENTERPRISE BLOCKS=True" .env 4. Launch the inference server inference server start -e .env The inference server start command auto-detects your hardware and pulls the matching image: CPU on most laptops, GPU when CUDA is available Jetson, NVIDIA-equipped server . Step 2: Configure folders and tags on your OPC UA server Before the workflow can write anything, the destination tags need to exist on your OPC UA server. Use the server’s native interface to create them: Ignition — open Designer, navigate to your tag provider, right-click → New Tag. Default port: 62541 . Kepware — use the Configuration tool to add tags under a channel/device Other servers — follow your vendor’s documentation Collect three pieces of info you’ll need in Step 4: - The endpoint URL e.g., opc.tcp://<server-host :62541 - The namespace URI string or numeric index - The NodeId format the server uses. String-based NodeIds Ignition-style require Node Lookup Mode: direct in the workflow block. The data type on each tag must match the Value Type field on the workflow block. Alternative: use Roboflow’s built-in OPC UA server If you don’t have an OPC UA server already, Roboflow’s edge devices ship with one you can add as a managed service. This path requires the Roboflow Deployment Manager , which is an Enterprise feature. On a Roboflow-managed edge device https://docs.roboflow.com/deploy/device-manager/setting-up/add-a-device?ref=blog.roboflow.com : - From the device dashboard, click Add Service → select OPC UA Server → submit - On the OPC UA Server card that appears, click Configure - Note the Namespace URI defaults to http://opcua.roboflow.run + Add Folder , then + Add Tag inside it set the data type to match what the workflow will write - Click Save Configuration Use the endpoint URL on the card opc.tcp://<device-ip :4840/opcua/server in your workflow. Step 3: Build the workflow Image input → Model → Optional Filter → Property Definition → OPC UA Writer Sink The Property Definition block reduces predictions to a single value that OPC UA can store, like a count or a boolean. Each value gets its own OPC UA Writer Sink block: one block per tag. Tag names must match exactly. Folder, tag name, casing, and separators all matter. A mismatch e.g., person present vs Person present, or / when the server expects . returns BadNoMatch and silently drops the write. Step 4: Configure the OPC UA Writer Sink block | Field | Value | |---|---| URL | URL of the OPC UA server to which data will be written. | Namespace | The OPC UA namespace URI or index used to locate objects and variables. For Roboflow's built-in OPC UA server: http://opcua.roboflow.run . | Object Name | For Ignition / string-NodeId servers: the bracketed parent path e.g., Sample Tags /Production . For Roboflow's built-in OPC UA server: the full folder.tag path e.g., production.defect count . | Variable Name | The name of the variable within the target object to be updated. For Ignition / string-NodeId servers: the tag name. For Roboflow's built-in OPC UA server: empty the full path went in Object Name . | Value | The value to be written to the target variable on the OPC UA server. $steps.<property definition step .output | Value Type | The type of the value to be written to the target variable on the OPC UA server. Must match the tag's declared type on the server. Supported types: Boolean , Double , Float , Int16 , Int32 , Int64 , Integer Int64 alias , SByte , String , UInt16 , UInt32 , UInt64 . | Node Lookup Mode | Method to locate the OPC UA node: hierarchical uses path navigation, direct uses NodeId strings for Ignition-style string-based tags . | Cooldown Seconds | The minimum number of seconds to wait between consecutive updates to the OPC UA server. | Keep Fire And Forget off False while you're setting things up. It surfaces real errors in the error status output. Turn it on for production. Step 5: Deploy and verify In the workflow editor, click Deploy → Local Server , enter http://localhost:9001 or your inference server's address , and click Connect . Run an image through the deployed workflow, or if you're on a Roboflow edge device, point a camera stream at it from the device dashboard. Run the workflow against a test image. If everything is wired correctly: - The OPC UA Writer Sink block's error status output is False - Its message output says the write succeeded - The tag value updates on your OPC UA server, visible in Ignition Designer, any OPC UA client, or the Roboflow device dashboard if using the built-in server Testing constraints The inference server must have network access to your OPC UA server. If they’re on different networks, bridge them via SSH tunneling or Tailscale before testing. For testing, the easiest setup is running inference on the same network as your OPC UA server Cite this Post Use the following entry to cite this post in your research: Kevin Seyedan /author/kevin/ . May 21, 2026 . Integrate Roboflow with OPC UA. Roboflow Blog: https://blog.roboflow.com/roboflow-opc-ua-integration/