Specifications

72 RSLinx – Training Guide
OPC over a network
Configuring Windows for DCOM
OPC between two PCs over a network uses Windows DCOM. The setup is slightly
different depending on the version of Windows you are running. Depending on the
server and client implementations of OPC, you may only have to make the following
configuration changes on the server. In the case of most RSI applications, these
changes should be made on the server and the client PC.
Win 95/98
DCOM does not ship as part of Windows 95 so it must be installed. DCOM for Windows
95 must be installed on both PCs. A self-extracting executable can be found on
http://www.Microsoft.com/com/dcom95. Download and run it.
DCOM installs as part of Windows 98 so this step is not necessary. Next, you must
have a domain controller on the network for WIN95/98 DCOM to work!
Setting up a Primary Domain Controller.
A Primary Domain Controller is a computer in a Windows NT Server Domain that
authenticates domain logons and maintains the directory database for a domain. The
primary domain controller tracks changes made to accounts of all computers on a
domain. It is the only computer to receive the changes directly. A domain has only one
primary domain controller.
First, you must determine if you have a domain controller on your network. Under
Windows 95 or 98 go to control panel and open Network Properties. Under the
configuration tab select Client for Microsoft Networks and click the Properties button. If
Login to Windows NT Domain is checked then you are probably on a network with a
domain controller. If so you can skip to the DCOM configuration section.. Check with
your network administrator if you are unsure.
Notes: (1) To use OPC over a network with RSLinx, you must have RSLinx
Gateway 2.0 or higher. RSLinx OEM or regular RSLinx will not do OPC
over a network.
(2) Remote OPC works best when RSLinx is run as a service.
• When running RSLinx as a service, do not open it as an application!