Introduction | OPC Technology | OPC Specifications
OPC Data Access Specification | DCOM Configuration | References

Introduction to OPC

OPC (OLE for Process Control) is an industrial 'de facto' open standard for real-time data communication.

OPC Servers manages all device-specific communication (SNMP, PerfMon) and provides data through a standard interface, while OPC Clients connects to servers to exchange information with field devices.

The picture below is an example of OPC communication. A field device (PLC) sending data to the OPC Server using a specific protocol and the OPC Server sending standard OPC data to the OPC client.

OPC Usual Network Configuration

OPC specifications are supported by the organization OPC Foundation and are under continuous evolution. OPC is based mainly on Microsoft COM/DCOM technology.

Software application tools that support OPC can be an OPC Client or OPC Server depending on the implemented functionality. Usually, OPC Servers are the applications that respond for one or several OPC Clients requests through OPC standard mechanisms for data reading, writing and updating.

Real-time data communications from shop floor to business application is best implemented through open OPC standard. XRatel tools were designed using a smart and high performance OPC Server for providing real-time data to industrial and business OPC Client applications.

Some examples of OPC Client applications are:

• Data Acquisition, Monitoring and Testing tools
• Human Machine Interfaces
• SCADA, DCS and Hybrid control systems
• Optimization tools
• PIMS
• MES solutions
• ERP packages
• Other emerging OPC tools