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OPC-UA Integration

Connect Konnect to OPC-UA servers to browse and monitor industrial automation data — PLCs, SCADA systems, and other OPC-UA enabled devices.

Overview

Section titled “Overview”

OPC Unified Architecture (OPC-UA) is the standard communication protocol for industrial automation. Konnect connects to any OPC-UA server and lets you:

  • Browse the server address space (nodes and tags)
  • Read current values from tags
  • Subscribe to tag changes for live monitoring
  • Visualise tag data on your dashboards

Adding an OPC-UA server connection

Section titled “Adding an OPC-UA server connection”

Step-by-step:

  1. Click OPC-UA Integration in the sidebar navigation.
  2. Click Add Server.
  3. Enter your server details:
    • Endpoint URL — e.g., opc.tcp://192.168.1.50:4840
    • Security Mode — None, Sign, or Sign & Encrypt
    • Security Policy — Basic256Sha256, Aes128Sha256RsaOaep, etc.
    • Username — Optional, depending on server authentication
    • Password — Optional
  4. Click Connect.

Once connected, Konnect establishes a session with the OPC-UA server and begins browsing the address space.

Browsing the address space

Section titled “Browsing the address space”

After connecting, Konnect displays the server’s address space as a navigable tree.

Step-by-step:

  1. The root node of the server appears in the tree view.
  2. Click the expand arrow (▶) next to any node to browse its children.
  3. Each node displays:
    • Display Name — Human-readable name
    • Node ID — The unique OPC-UA identifier (e.g., ns=2;s=Temperature)
    • Node Class — Object, Variable, Method, etc.
    • Data Type — For variable nodes: Int32, Double, String, Boolean, etc.
    • Current Value — For variable nodes: the current value read from the server
  4. Click a variable node to view its details and current value.

Node types

Section titled “Node types”
Node ClassIconDescription
Object📁Container for other nodes — browse deeper to find variables
Variable📊A data point you can read, subscribe to, and chart
Method⚙️A callable method on the server (read-only in Konnect)

Reading tag values

Section titled “Reading tag values”

Step-by-step:

  1. Browse to a variable node in the address space tree.
  2. Click the node to read its current value.
  3. The value, data type, timestamp, and status code are displayed.

You can also ask Kai:

Read the current value of OPC-UA node ns=2;s=Temperature

Subscribing to tag changes

Section titled “Subscribing to tag changes”

For live monitoring, subscribe to tag changes so Konnect receives updates whenever a value changes.

Step-by-step:

  1. Browse to a variable node.
  2. Click the Subscribe button next to the node.
  3. The node is added to your active subscriptions.
  4. Value updates appear in real time in the tag list.
  5. Drag the subscribed tag onto the dashboard to create a live chart.

Managing subscriptions

Section titled “Managing subscriptions”
  • View all active subscriptions in the Subscriptions panel on the OPC-UA page.
  • Click Unsubscribe to stop receiving updates for a specific tag.
  • Subscriptions persist across page navigation but are reset when Konnect restarts.

Using OPC-UA data in dashboards

Section titled “Using OPC-UA data in dashboards”

Once subscribed to OPC-UA tags, the data is available in the Data Sources explorer:

  1. Expand the OPC-UA connection in the left panel.
  2. Browse subscribed tags.
  3. Drag a tag onto the dashboard to create a live-updating chart.
  4. Or ask Kai: Create a line chart of ns=2;s=Temperature over the last hour.

Troubleshooting

Section titled “Troubleshooting”
IssueSolution
Connection refusedCheck the endpoint URL and ensure the OPC-UA server is running and reachable
Security policy errorVerify the security mode and policy match the server’s configuration
Certificate errorSome servers require certificate trust — check your server’s documentation
Empty address spaceThe server may require authentication — provide username and password

Next steps

Section titled “Next steps”