Introduction to Modbus OPC Server

 

The ICONICS Modbus OPC Server is an OPC-compliant server that serves data to OPC clients. The Modbus OPC server was implemented using advanced programming concepts of the current version of the OPC specification for use in developing next generation industrial software applications.

 

The ICONICS Modbus OPC Server communicates with OPC clients and real time Modbus Ethernet I/O devices. This Modbus OPC server is based on the popular Modbus protocol and can be connected to real world Modbus compatible I/O hardware. The Modbus OPC Server/Client is an ideal way to learn about the new emerging OPC standard and can also be used to test other OPC-compliant clients.

 

Key Features of Modbus OPC Server Include:

NOTE: The version of Modbus OPC Server v3.6 installed with ICONICS' GENESIS64 V10.95 HMI/SCADA suite contains integrated Performance Counters for use with new System Health Monitoring features. [See the GENESIS64 main Help for more information on System Health Monitoring].

 

The standalone installation of Modbus OPC Server v3.6 does not contain these Performance Counters.

 

New Features in Version 3.6 Include:

The Modbus OPC Server product contains two parts: a user interface configuration module and the actual OPC server, the runtime module.

 

The configuration module allows you to create a database that holds configuration data of the tags. Such as the tag name, the ranging, and the alarm settings. The runtime module uses a runtime database to access the actual values of the tags configured. Structures of both databases are indicated in the following sections.

 

Changes made to the configuration are accepted only after a restart of the OPC server. However, changes made to the runtime database are accepted online.

What Is OLE for Process Control?

OLE for Process Control (OPC) is a standards-based approach for connecting data sources (e.g., PLCs, controllers, I/O devices, databases, etc.) with HMI client applications (graphics, trending, alarming, etc.). It enhances the interface between client and server applications by providing a universally supported and well-documented mechanism to communicate data from a data source to any client application. Included are not only a detailed guide on how to pass the data, but also specific information on other attributes to supplement those data, such as range information, data type, quality flags, and date and time information. The figure below shows the OPC Architecture, which was introduced by the OPC Foundation. By following the OPC Architecture, a device needs only one standard driver, which is an OPC-compliant server. All OPC-compliant client applications can then be connected to that device, either locally or over a network. Furthermore, connections can be made to more than one OPC server at the same time.

 

OPC-Based Client-Server Architecture
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Any OPC client application can connect to any OPC server. In other words, OPC offers true Plug-and-Play capability in the fields of HMI and industrial automation. OPC server types include OPC Data Access (DA), OPC Alarm and Events (AE), and OPC Historical Data Access (HDA).

 

See Also:

Starting the Modbus OPC Server Configurator