2.1.6   OPC Service installation

For remote OPC servers

If a SCADA node is to access the OPC server of a remote computer, then the OPC Service must be installed on that remote OPC Server computer.  No Hardkey or license is required for this option.  This is not an OPC Server.  It is a service (the WebAccess Network Service) that allows the WebAccess Project Manager to communicate to a remote OPC Server that is not part of a SCADA node.

Install only OPC service software, Installation Option 4, is intended for a remote OPC server that is not on the same computer as a SCADA node.

The OPC service is a configuration tool that allows Tags to be imported from a remote OPC Server into the WebAccess Project Manager using the Internet or a TCP/IP communications network.  Don't confuse this "Service" with "Server".  The  "OPC service" is not an "OPC server".

OPC is a communication protocol used frequently in Process Control.  Many PLC and automation equipment manufacturers supply OPC Servers rather than provide direct access using a communication protocol.  There also 3rd party software vendors that supply OPC Server software.  SCADA nodes communicate via OPC to the PLCs, Controllers and IO.  Technically, the SCADA node is an OPC client that communicates to software that is an OPC Server. 

The OPC Server software is usually on the same PC as the SCADA node. When we install the SCADA node software, we also install the necessary OPC services that allow the project node database to import tags from the OPC Server.  However, it is possible that the OPC server is not on the SCADA node. The SCADA node can communicate with a "remote" OPC Server.  The problem is the Project Manager; in order to import tags from the OPC Server to the Project Manager (the project node), an OPC Service is needed on the OPC Server to communicate with the Project Node database.

If the OPC Server is on a PC that is not a SCADA node, then use this option: OPC Service Only to install an OPC service on the PC with the OPC Server.  This will enable the Project Manger to import tags from the remote OPC server.

OPC Service software installation (Setup.exe)

To install the WebAccess OPC Service software on a PC with a remote OPC Server:

1.      Insert the WebAccess CD into your CD-ROM drive.

The installation program automatically starts up if autorun is enabled on the PC. If the Install program does not start automatically, open explore, browse to the CD and double click on setup.exe

2.      You will see the Welcome to the Installation CD html page.

3.      Select -Install Project and SCADA node (even though you are installing only the OPC Service)

(Optionally, download and run the WebAccessUSANode.exe from the FTP site).

4.      The Install Shield Program starts.

5.      A Welcome to Install Shield Screen is displayed.
 To continue, click Next.

6.      The WebAccess License Agreement displays. Please carefully read the License Agreement. Clicking No will end Setup. To accept the License Agreement and
to continue with Setup, click Yes.          

7.      Enter your Customer Information (user name and company).
To continue, click Next.

8.      Select Options to install.  Different questions will be asked depending on which option is picked.  This assumes you want to install the remote OPC Service on a PC with an OPC Server.  The OPC Service allows remote browsing of OPC Servers using the TCP/IP protocol.

Select OPC Service Only.

9.      Destination - Folder where setup will install WebAccess OPC Service program files.  To continue, click Yes.

Note - It is recommended to accept the default directory (drive:\WebAccess\Node) unless you are very experienced user and have a good reason. If you are changing the default location, type the entire path (DO NOT ENTER ONLY A DRIVE LETTER).

10.  Enter a Remote Access Code.  This is HIGHLY RECOMMENDED.  It will prevent unauthorized users from hijacking your Project Node (Web Server) or SCADA node.  32 characters maximum.  You can only modify this Remote Access Code using the installation program.

11.  If data must pass through a Fire Wall, enter the Firewall TCP/IP Primary Port  (i.e. firewall port).

Note - 0 = the default port number (4592)

If you are not using a firewall, accept the default (0).
To continue, click Next.

12.  WebAccess will install files to the directories above.

13.  Install Wizard Complete.
Select Yes, I want to restart my computer now.

To continue, select Finish.

TAfter reboot, you should see the WebAccess Icon  in the taskbar next to the system clock.