Documentation

Connection Status

This port outputs the state of the client-server connection as an array of data type UINT32 and length 3. The first index is the OPC UA session state. The available values are:

Code	Description
0	UA_SESSIONSTATE_CLOSED
1	UA_SESSIONSTATE_CREATE_REQUESTED
2	UA_SESSIONSTATE_CREATED
3	UA_SESSIONSTATE_ACTIVATE_REQUESTED
4	UA_SESSIONSTATE_ACTIVATED
5	UA_SESSIONSTATE_CLOSING

The second index is the OPC UA secure channel state. The available values are:

Code	Description (before v9.9.1)	Description
0	UA_SECURECHANNELSTATE_FRESH	UA_SECURECHANNELSTATE_CLOSED
1	UA_SECURECHANNELSTATE_HEL_SENT	UA_SECURECHANNELSTATE_REVERSE_LISTENING
2	UA_SECURECHANNELSTATE_HEL_RECEIVED	UA_SECURECHANNELSTATE_CONNECTING
3	UA_SECURECHANNELSTATE_ACK_SENT	UA_SECURECHANNELSTATE_CONNECTED
4	UA_SECURECHANNELSTATE_ACK_RECEIVED	UA_SECURECHANNELSTATE_REVERSE_CONNECTED
5	UA_SECURECHANNELSTATE_OPN_SENT	UA_SECURECHANNELSTATE_RHE_SENT
6	UA_SECURECHANNELSTATE_OPEN	UA_SECURECHANNELSTATE_HEL_SENT
7	UA_SECURECHANNELSTATE_CLOSING	UA_SECURECHANNELSTATE_HEL_RECEIVED
8	UA_SECURECHANNELSTATE_CLOSED	UA_SECURECHANNELSTATE_ACK_SENT
9		UA_SECURECHANNELSTATE_ACK_RECEIVED
10		UA_SECURECHANNELSTATE_OPN_SENT
11		UA_SECURECHANNELSTATE_OPEN
12		UA_SECURECHANNELSTATE_CLOSING

The third index is an error code. A valid connection is indicated by

• OPC UA session state = ACTIVATED and

• OPC UA secure channel = UA_SECURECHANNELSTATE_OPEN and

• Error = 0

This block does not have any input ports.

Station ID

Apply the Station ID of the corresponding Setup block. Must range between 0 and 65535.

Connection ID

The Connection ID is used to assign Read and Write blocks to a particular client-server connection. Connection IDs range between 0 to 65535 and must be unique along all Connections blocks of the client (these blocks have the same Station ID).

Remote Address

Enter the IP address or URL of the remote OPC UA server. If the Remote TCP Port parameter is 0, the remote address must be a URL. In all other cases, the remote address must be an IP address. Examples:

Remote TCP Port 4840 and Remote Address '192.168.1.50' prompts the client to connect to port 4840 at 192.168.1.50

Remote TCP Port 0 and Remote Address 'opc.tcp://192.168.1.51:4841' prompts the client to connect to port 4841 at 192.168.1.51

Remote TCP Port

Enter the TCP port the remote OPC UA server is listening on for connection requests.

Sample Time

Defines the base sample time at which this driver block gets its sample hit. This parameter can also be set to -1 for inherited sample time. The units are in seconds.

Security Policy

Select the security policy of the server endpoint to which the client should connect.

Security Mode

Select the security mode of the server endpoint to which the client should connect. If the security policy is None, the security mode must also be None.

User Token Policy

Select the user token policy for user authentication. If Username is selected, enter the user credentials in the Username and Password parameters. Furthermore, you must provide a certificate and a private key as the remote server's policy may require username and password encryption.

Certificate

Define the location of the public application instance certificate on the host PC. The file must be an X509 DER file with extension *.cer. During the build process, the file will be packed into the real-time application and transferred to the target machine. The certificate is required for security policies other than None. The X509v3 Subject Alternative Name property of the certificate file must match the character array entered in the Application URI parameter. You can use the certificates included in the OPC UA product examples.

Data type: Character array

Default value: ''

Private Key

Define the location of the private key file on the host PC. The file must be a PEM file with extension *.pem and must relate to the certificate. During the build process, the file will be packed into the real-time application and transferred to the target machine. The private key is required for security policies other than None. You can use the private keys included in the OPC UA product examples.

Data type: Character array

Default value: ''

Username

Specify the user name with which the client should log in to the server.

Data type: Character array

Default value: ''

Password

Enter the password associated with the username.

Data type: Character array

Default value: ''

Application URI

The Application URI is a common identity property of all OPC UA devices. When using certificates, the Application URI must match the X509v3 Subject Alternative Name property of the certificate.