Yokogawa / Exaopc (CENTUM OPC Server)

Source: Yokogawa Official website
(https://www.yokogawa.com/in/)

Exaopc is Yokogawa's OPC server software for exchanging data between CENTUM production control systems and OPC client applications. It connects directly to CENTUM through Vnet/IP, providing an interface between the control system and applications that use plant data.

For an Indian plant extending its existing CENTUM installation, package selection starts with the receiving application. Identify the interface it requires, then match the Exaopc release to the installed control system and computing environment.

Key Takeaways

• Select the OPC Classic or OPC UA package to match the receiving application's interface.
• Check compatibility by package and release, including the Windows edition and deployment platform.
• Specify the client application when planning redundancy; supported combinations have restrictions.
• Use historical deployments to understand connection roles, then validate the proposed configuration against current specifications.

Exaopc OPC Classic and OPC UA Packages

Source: Yokogawa Official website
(https://www.yokogawa.com/in/library/resources/yokogawa-technical-reports/redundant-opc-server-configured-by-exaopc-rd-virtual-opc-server/)

Yokogawa's R3.82 announcement in November 2025 introduced the Exaopc OPC UA Interface Package alongside the existing OPC Interface Package. Choose between them by the required data interface, rather than treating every Exaopc function as available through both packages.

A requirement for historical-data access or batch integration needs a package-specific review. Establish which service the client will call before defining the connection or requesting a quotation.

Challenges Exaopc Can Help Solve

Sharing CENTUM Data with Plant Information Systems

Yokogawa identifies Exaquantum PIMS and general-purpose OPC applications among Exaopc's connection targets. Projects can use this interface to make CENTUM data available to the selected client.

For a historian or production-information project, define the variables, events and access permissions the application needs. Include whether the connection is for monitoring or also requires approved write access.

Keeping Tag Information in Step with Engineering Changes

The Classic package's equalization function updates function-block information after engineering changes are loaded into the FCS. The client can browse the tag list acquired by Exaopc.

Include representative tag additions and changes in acceptance testing. Verify how the receiving application handles them before using the same approach across the plant.

Managing Data Access Loads on the Control System

Exaopc's documented traffic-control function restricts access volume to avoid exceeding the accessible data rate. This addresses concentrated loads on CENTUM control stations and control buses.

Prepare the requested tag count and acquisition intervals before sizing the connection. Test the combined client workload, including the demand expected after rollout.

Where Is Exaopc a Good Fit?

Evaluate Exaopc when a project must connect an existing CENTUM system to an OPC-based information application. A plant retaining a Classic client should assess that connection separately from a project introducing a UA client.

Start with an inventory of the installed CENTUM release and receiving applications. For a site with several control-system vendors, map each required connection before deciding whether a CENTUM-focused interface covers the whole project.

Key Specifications and Compatibility

Windows support depends on the exact edition, release and patch level. The examples above come from different package documents and are not a single shared compatibility list.

For Classic redundancy, Exaopc-RD monitors two servers and switches the client connection after a failure. The current general specification limits this arrangement to specified Exaopc server models and Exaquantum or Exapilot clients. Confirm the complete server-client combination before including it in a recovery design.

Deployment Example: Connecting CENTUM to a PI System

Yokogawa's Saudi Aramco Southern Area gas-oil separation plant modernization reference lists an ExaOPC station providing the interface to a PI station in a typical project configuration. The same configuration includes a CENTUM CS 3000 R3 DCS.

The published completion date is 2007. This example demonstrates Exaopc's role in a historical CENTUM-to-PI connection. It predates the new UA package and should be used as a reference for the integration role, with current compatibility established separately.

Licensing, Evaluation and Support in India

Use the Yokogawa India product page's quotation and technical-support options to discuss a proposed deployment. Provide the CENTUM release, client interface, required data services, tag workload and redundancy plan so the supplier can identify the package and configuration.

Yokogawa's maintenance specification covers both Exaopc packages and requires an Annual Maintenance Contract when covered software licenses are ordered. Software maintenance and on-site system maintenance have different scopes; request a breakdown of licensing, maintenance and commissioning costs.

For evaluation, ask Yokogawa India about an available demonstration or project-specific test. Establish the evaluation conditions and acceptance criteria before scheduling work, including data updates, engineering changes and recovery after a connection loss.

Manufacturer Information

Yokogawa Electric Corporation supplies measurement, control and information solutions for industrial operations. For local product and project enquiries, use Yokogawa India's official sales and support channels.