OPC UA Automation: Read, Write, and Browse Industrial Nodes

OPC UA is the backbone of modern industrial automation — powering PLCs, SCADA systems, HMIs, sensors, gateways, and factory‑floor communication. The OPC UA Connector brings this industrial capability directly into your workflows, allowing you to read live values, write setpoints, and browse node hierarchies from any compliant OPC UA server.

The connector definition states that it can "read, write, and browse OPC UA nodes on industrial servers and PLCs." It supports on‑prem execution, secure sessions, anonymous or username authentication, and full access to OPC UA data models.

Step 1: Connect to an OPC UA Server

Drag an OPC UA Read, OPC UA Write, or OPC UA Browse node onto the canvas. Configure the connection settings:

• endpointUrl — e.g., opc.tcp://192.168.1.10:4840
• securityMode — None, Sign, or Sign & Encrypt
• username / password — optional credentials
• timeoutMs — session timeout

The connector automatically creates a secure OPC UA session, loads certificates, and handles namespace resolution.

Step 2: Read a Node Value

Use the OPC UA Read node to retrieve the current value of any OPC UA variable. Configure:

• nodeId — e.g., ns=2;s=Temperature or ns=2;i=1001

On success, the node returns:

• value — decoded Variant value
• nodeId — resolved NodeId
• statusCode — OPC UA status
• sourceTimestamp — timestamp from the server

This is ideal for reading sensor values, machine states, counters, or telemetry from PLCs.

Step 3: Write a Node Value

The OPC UA Write node allows you to send setpoints, commands, or configuration values to a PLC or industrial device.

Configure:

• nodeId — target variable
• value — text, number, boolean, or JSON
• valueType — auto, boolean, int32, double, string
• mergeInput — merge upstream payload automatically

Outputs include:

• value — written value
• statusCode — write result
• writtenAt — timestamp

This is perfect for adjusting setpoints, toggling outputs, writing configuration parameters, or controlling industrial processes.

Step 4: Browse OPC UA Nodes

Use the OPC UA Browse node to explore the server’s address space. You can specify:

• browseNodeId — starting point (default: i=85, Objects folder)
• maxResults — limit results

The node returns:

• nodes — array of { displayName, nodeId, nodeClass }
• count — number of discovered nodes

This is ideal for mapping devices, discovering variables, or building dynamic workflows.

Step 5: Build Industrial Automations

Once OPC UA data enters your workflow, you can combine it with any other connector:

• Trigger alerts when values exceed thresholds
• Store telemetry in Google Sheets or databases
• Send commands based on sensor readings
• Integrate PLC data with dashboards
• Run conditional logic based on machine states

OPC UA becomes a powerful entry point into your automation ecosystem.

Example Workflow

Here’s a complete OPC UA automation you can build:

1. Read a temperature node from a PLC.
2. If the value exceeds a threshold, write a new setpoint.
3. Log the reading to a database.
4. Send a Telegram alert to operators.
5. Store historical values for trend analysis.

All of this runs automatically — no manual intervention required.

What's Next?

Try combining OPC UA with connectors like Serial Bus, S7 PLC, HTTP, or WebSocket. Build full industrial dashboards, automated control loops, or real‑time monitoring systems.

OPC UA unlocks powerful industrial automation — and this connector makes it accessible, safe, and deeply integrated.