1

In the Devices tree, double-click MyController.

2

Select the OPC UA Server Configuration tab.

OPC UA Server Enabled

Enabled/ Disabled

Enabled

This checkbox is used to enable or disable the OPC UA Server on the controller.

Security Settings

Disable anonymous login

Enabled/ Disabled

Disabled

By default, this checkbox is cleared, meaning that OPC UA clients can connect to the server anonymously. Select this checkbox to require that clients provide a valid user name and password to connect to the OPC UA server.

NOTE: Anonymous login is disabled when User Rights are activated, regardless of the state of this parameter.

Security Policy

None

Basic256

Basic256Sha256

–

This drop-down menu allows you to secure your exchanges by signing and encrypting the data you send and receive.

Message Security

None

Sign

SignAndEncrypt

–

The messages are related to the Security Policy selected.

Server Configuration

Server port

0...65535

4840

The port number of the OPC UA server. OPC UA clients must append this port number to the TCP URL of the controller to connect to the OPC UA server.

Max. subscriptions per session

1...100

20

Specify the maximum number of subscriptions allowed within each session.

Min. publishing interval

200...5000

1000

The publishing interval defines how frequently the OPC UA server sends notification packages to clients. Specify the minimum time that must elapse between notifications, in ms.

Max. monitored items per subscription

1...1000

100

The maximum number of monitored items in each subscription that the server assembles into a notification package.

Min. KeepAlive interval

500...5000

500

The OPC UA server only sends notifications when the values of monitored items of data are modified. A KeepAlive notification is an empty notification sent by the server to inform the client that although no data has been modified, the subscription is still active. Specify the minimum interval between KeepAlive notifications, in ms.

Max. number of sessions

1...4

2

The maximum number of clients that can connect simultaneously to the OPC UA server.

Identifier type

Numeric

String

Numeric

Certain OPC UA clients require a specific format of unique symbol identifier (node ID). Select the format of the identifiers:

oNumeric values

oText strings

Diagnostic

Enable trace

Enabled/disabled

Enabled

Select this checkbox to include OPC UA diagnostic messages in the controller log file. Traces are available from the Log tab or from the System Log File of the Web Server.

You can select the category of events to write to the log file:

oNone

oError

oWarning

oSystem

oInfo

oDebug

oContent

oAll (default)

Sampling rates (ms)

200...5000

500

1000

2000

The sampling rate indicates a time interval, in milliseconds (ms). When this interval has elapsed, the server sends the notification package to the client. The sampling rate can be shorter than the publishing interval, in which case notifications are queued until the publishing interval has elapsed.

Sampling rates must be in the range 200...5000 (ms).

Up to 3 different sampling rates can be configured.

Double-click on a sampling rate to edit its value.

To add a sampling rate to the list, right-click and choose Add a new rate.

To remove a sample rate from the list, select the value and click