Full Answer
Why can't I connect to a remote OPC Server?
In any case, if you know the identity of the remote OPC server (either through a remote browse or by simply "knowing" the correct GUID), but are still unable to establish the OPC connection, there can be several factors responsible for failures. If the OPC server is set to run as a Windows Service, it is possible it was disabled.
Why can’t opcenum browse on a remote computer?
OpcEnum is only able to browse for OPC servers on the machine on which it is running. Therefore, OpcEnum cannot browse a remote computer, even if a copy of OpcEnum is present on your own computer. OPC Expert will automatically inform you if OpcEnum is not installed on your computer. It will also repair the problem.
How can OPC expert help you?
To get a deeper understanding of OPC, DCOM, and the diagnosis of all common problems OPCTI highly recommends you take time to get formal OPC training. This will enable you to structure your OPC knowledge to help you reduce your short and long-term project costs. OPC Expert can help you troubleshoot and diagnose OPC communication problems.
Where can I find the opcenum for the local computer?
The Computer Management window for the local computer is displayed. "Computer Management (Local)" is displayed at the root of the console tree. In the console tree, expand "Services and Applications", and click the Services container. Look for OpcEnum in the right-hand window pane.
How do I connect to remote OPC Server?
If you use OPC DA, you have to do OPC DCOM settings. And if you are connecting to the remote PC, make sure you have the same user name in both local and remote machine and this user have rights to access the OPC enum service. Check this link, it contains all the details related to opc remote settings.
What is DCOM and OPC?
OPC technology relies on Microsoft's COM and DCOM to exchange data between automation hardware and software; however it can be frustrating for new users to configure DCOM properly. If you have ever been unable to establish an OPC connection or transfer OPC data successfully, the underlying issue is likely DCOM-related.
What is OPC used for?
Open Platform Communications (OPC) is an interoperability standard for the secure exchange of industrial automation data. It is designed to be platform-dependent so devices from different vendors can exchange information.
Does OPC use DCOM?
OPC clients and servers use COM to communicate with each other over the same machine and use DCOM to communicate directly with each other across a network.
What ports does OPC use?
When an OPC client connects to an OPC server, it connects to port 135 (the RPC port mapper), which assigns one TCP port and one UDP port to the component.
What ports does DCOM use?
DCOM uses Port 135 to establish communication. Once the OPC Client and Server are able to communicate, they will negotiate new port numbers for communication dynamically.
Does OPC use TCP?
OPC UA has become completely platform-independent through TCP/IP and web protocols for communication.
What is OPC and its types?
In an OPC Client / OPC Server Architecture, the OPC Server is a Slave while the OPC Client is the Master. Communication between the OPC Client and OPC Server is bi-directional meaning the OPC Clients can read from and write to OPC Servers. There are four types of OPC Servers defined by the OPC Foundation.
What is an OPC client?
An OPC Client is a software module that enables applications to acquire data from an OPC Server or conduct supervisory control using an OPC Server. OPC is based on client/server architecture. OPC Client applications can be used for data acquisition.
What is OPC UA protocol?
OPC Unified Architecture (OPC UA) is a machine-to-machine communication protocol used for industrial automation and developed by the OPC Foundation. The OPC UA platform in an platform-independent service-oriented architecture that integrates individual OPC Classic specifications into an extensible framework.
What is OPC enum?
OPCEnum is a program that scans your registry for a list of OPC Servers on your computer OPCEnum needs to be able to run on the computer where it resides. Therefore, ensure to check Run application on this computer. Security Tab. There are 3 options on the Security tab that need to be set. Launch Permissions.
What is OPC DA and UA?
OPC UA is the Unified Architecture of OPC. Specification doesn't says anything about platform, OS etc. OPC DA, is older version of OPC specification. Where there was data modelling (not to a greater extent like OPC UA has).
What does DCOM stand for?
Distributed Component Object ModelDCOM is an acronym that stands for Distributed Component Object Model. DCOM is a proprietary Microsoft software component that allows COM objects to communicate with each other over the network.
What is DCOM in Windows?
The Distributed Component Object Model (DCOM) is a protocol that enables software components to communicate directly over a network. Previously named "Network OLE," DCOM is designed for use across multiple network transports, including Internet protocols such as HTTP.
What is OPC interface?
OPC is a software interface interoperability standard that allows secure and reliable exchange of data between Windows programs and industrial hardware devices. It is platform-independent and ensures the continuous flow of information across multiple vendor devices.
What is OPC DA and UA?
OPC UA is the Unified Architecture of OPC. Specification doesn't says anything about platform, OS etc. OPC DA, is older version of OPC specification. Where there was data modelling (not to a greater extent like OPC UA has).
How to modify OPC server?
Right-click the OPC server you want to modify and choose Properties. The <Selected OPC Server> Properties dialog box appears.
How to allow remote access to a user?
Select the user labeled Everyone, and then select the Allow check box for Remote Access.
How to run dcomcnfg?
To launch the DCOM configurator: 1 From the Start menu, select or type Run. The Run dialog box appears. 2 Type: dcomcnfg and click OK.
How many permissions are there in COM Security?
Click the COM Security tab. There are four permissions on this dialog box.
How to allow DAC access to a file?
Select the DAC group and select the Allow check box for Access Permission.
What group should OPC users be in?
GE recommends that all OPC Client users be members of the Administrators group. To facilitate this, GE recommends creating a users group to contain individual users that need to access remote OPC servers.
Where is OPCenum located?
OPCENUM must reside on the remote machine with the OPC server. While most OPC Server applications install and register this file, some do not. You can download this file from www.opcfoundation.org. Currently it is contained within the OPC Core Components 2.00 Redistributable 2.30.msi file. After you download OPCENUM, run the .msi file.
