Create and configure the interface instance

For each OPC server intended to exchange data with the PI System, you must create at least one instance of the PI OPC interface. For each instance you create, settings are stored in a separate Windows command file (a .bat file) in the PI OPC interface installation directory.

Tip: Configure multiple instances of the PI Interface for OPC DA with unique interface ID (id) and point source (ps) startup parameters to more easily identify where the data written to Data Archive originated, and trace any problems that arise.

1. Launch PI ICU and select Interface > New from BAT file.

2. Browse to the interface installation directory (default %PIPC%\Interfaces\OPCInt), select OPCInt.bat_new, and then select Open.

   The Select PI Host Server window opens.

3. Specify the Data Archive and select OK.

   PI ICU displays the settings of the new instance of the interface.

4. Configure the basic settings as follows:

   • General tab

     Point source	ID	Scan Class
     Use OPC or a point source not already in use.	Use 1 or a numeric ID not already in use by another instance of the interface.	Set to desired scan frequency. Scan class 1 is reserved for advise tags. When defining multiple scan classes, you can spread the server workload using offsets.

   • OPCInt page

     Select the List Available Servers button, then select your OPC server from the drop-down list of servers. If the server resides on another machine, specify the node name or IP address in the Server Node field before listing the available servers.

     Note: Certain OPC servers may refuse remote connection attempts. If the Server Node field is blank or set to LocalHost (case insensitive), the interface will treat the server as though it is local. If anything else is used in the Server Node field, the connection will be treated as remote.

   • Security Parameters tab

     Most OPC servers do not support OPC security. Verify that your OPC server supports security before enabling this option. If your OPC server requires clients to use OPC security, enable OPC security and select NT security or Private OPC security, then select OPC Security Credentials. This opens a separate file with a .cred extension. Fill in the corresponding OPCUser and OPCPassword fields and save the file. Upon startup of the interface the OPCUser and OPCPassword fields are replaced with asterisks. A corresponding Windows Credential is created for the OPC Security Credentials. The Windows Credential is linked to the account that the interface is running under. The OPC Security Credentials file path corresponds to the parameter /credfilepath.

     Note: Previously set credentials will no longer be valid, they must be reentered using the OPC Security Credentials file.

     If your OPC server supports both NT security and private OPC security, AVEVA recommends using NT security. This option authenticates the interface to the server using your Windows domain account and avoids transmitting a password over the network. If you must use private OPC security, configure DCOM using the Packet Privacy authentication level to ensure the password is encrypted in transit. See the DCOM Security and Configuration Guide for more details.