Welcome to the AVEVA™ PI OPC UA Server

The AVEVA PI OPC UA Server provides structured data access leveraging the Open Platform Communications Unified Architecture (OPC UA) with the ability to:

• Read data

• Write data

• Subscribe to data

The PI OPC UA Server adheres to the IEC 62541 OPC UA specification, which defines a platform-independent framework for secure and reliable data exchange between industrial systems. The server is compliant with version 1.04 of the specification.

Any OPC UA client that also supports the IEC 62541 standard can connect to the PI OPC UA Server.

Additionally, multiple PI Systems, when defined in the Known Servers Table (KST), can connect to the PI OPC UA Server.

Note: While it is possible to install PI OPC UA service on the same computer as the Data Archive, AVEVA does not recommend this because it might lead to resource contention between PI OPC UA Server and the Data Archive. This can negatively affect the performance of both systems.

OPC UA Features

Current Data Access

Clients can access current PI System values using OPC UA read and write operations. The server supports the following access patterns:

• Polling – Clients request data from the server.

• Subscriptions – The server sends updates to clients when subscribed values change.

Historical Data Access

Clients can retrieve archived data from the PI System. The PI OPC UA Server supports the following historical read operations:

• Reading raw historical values

• Reading aggregated values over a time range, including averages, minimums, and maximums (see Historical data reads for more detail).

Unsupported OPC UA services

The following OPC UA services are not supported:

• Methods – Client-triggered function execution on the server

• Alarms and Conditions – Event-based notifications and alarm management

Authentication

The PI OPC UA Server supports the following authentication methods:

• X.509 certificate authentication

• Anonymous authentication (disabled by default)

Username and password authentication is not supported.