27 March 2008

OPC helps standards work together

By Jim Pinto

Standards are intrinsically difficult to implement and adopt. In the industrial automation business, OPC is a unifying standard that allows true interoperability.

Industrial automation is served by many different suppliers, each offering products and systems, which support different standards. However, the diversity of industrial applications means no single company can provide the broad spectrum of products required.

Typically, end users must choose from a mix of proprietary products and technologies with limited possibilities for integration of overall system communications. This is the old nemesis of "islands of automation," which the industry has been trying to overcome. However, end users continue to have multiple vendor dependencies, and their systems become a service and maintenance nightmare.

What end users need is the freedom to choose the best products from many different suppliers, with network interfaces or "glue" that makes everything play together beyond proprietary boundaries. That "glue" is OPC.

OPC is open connectivity through the creation and maintenance of open standards specifications. The OPC Foundation is an independent, international organization that brings together leading suppliers, solution providers, and end users in factory automation and process control markets to provide interoperability between products from cooperating suppliers.

The acronym OPC originates from an earlier organization: "OLE for Process Control." OLE was "Object Linking and Embedding," which (in the past) was Microsoft's software mechanism for linking different product protocols. Today, OPC involvement has gone beyond just process control, to factory automation and other industrial applications, and indeed is now extending to enterprise systems.

The OPC Foundation has been able to work more quickly than many other standards groups because it utilizes cooperation between OPC members to make their products interoperable through extensions of their own existing standards. Other industry committees, which have tried to define standards from the ground up, have found it more difficult to reach consensus between competing vendors.

OPC assures interoperability by creating and maintaining open specifications that standardize the communication of acquired process data, alarm and event records, historical data, and batch data between production devices in multi-vendor enterprise systems. Production devices include sensors, instruments, PLCs, RTUs, DCSs, HMIs, historians, trending subsystems, alarm subsystems, and the like.

Collaboration between suppliers is the key to pulling multiple "open" standards into unified open platform architectures. OPC monitors technologies and trends, and collects feedback from end users and solutions providers to help adapt and improve performance, and ensure linkages between products from different suppliers.

Today OPC has over 400 member companies, and membership should grow to 1,000 over the next few years. Already, more than 2,500 different companies use and build about 15,000 OPC compliant products.

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Behind the byline

Jim Pinto is an industry analyst and founder of Action Instruments. You can e-mail him at jim@jimpinto.com or view his writings at www.JimPinto.com. Read the Table of Contents of his book, Pinto's Points, at www.jimpinto.com/writings/points.html.