Unified Automation / UaGateway

Source: UaGateway Official Website
(https://documentation.unified-automation.com/uagateway.html)

UaGateway from Unified Automation GmbH connects Classic OPC applications with OPC UA systems. Manufacturing teams in India can use it to connect new applications to existing OPC servers or retain HMI/SCADA clients when upgrading the systems behind them.

Equipment data reaches UaGateway through an existing OPC server or a controller's own OPC interface. Direct PLC communication depends on that underlying connection.

Key Takeaways

• Use a wrapper to expose Classic OPC data to UA clients, or a proxy to connect legacy clients to UA servers.
• A tunnel between Classic OPC applications on separate computers requires UaGateway at both ends.
• Select feature keys according to whether the application needs live data, alarms, history, custom mapping or tag linking.
• Use the trial to verify compatibility and recovery after a connection failure.

Challenges UaGateway Can Help Solve

Source: UaGateway Official Website
(https://documentation.unified-automation.com/uagateway/1.3.1/html/index.html)

Connecting Classic OPC and OPC UA Applications

As a wrapper, UaGateway connects locally to a Classic OPC server and exposes its data to OPC UA clients. As a proxy, it makes data from OPC UA servers available to a legacy OPC DA client, such as an HMI or SCADA application. Either approach allows one side of a connection to be upgraded while the other remains in use.

Replacing Remote DCOM with OPC UA Tunnelling

A tunnel uses two UaGateway installations, one beside each Classic OPC application. The applications communicate locally through COM; the gateways exchange data over OPC UA with authentication and encryption.

The connection between computers therefore uses OPC UA instead of remote DCOM. Firewall rules, certificate trust and user permissions remain part of the network configuration.

Aggregating Multiple OPC Servers into One Access Point

UaGateway combines data from multiple underlying OPC servers into one OPC UA access point. Upper-level applications connect to the gateway rather than maintain a separate connection to each source.

Recovery from a source-server or gateway failure needs a separate design. Aggregation does not, by itself, provide failover.

What Types of Sites Is UaGateway Suitable For?

UaGateway addresses plant upgrades where an existing OPC interface must remain available during migration. Examples include adding an MES connection to a production line or replacing a data source while keeping the existing SCADA client.

A site with separate OPC servers for different production areas can also consolidate access through a gateway. Compatibility depends on those servers' interfaces, rather than the equipment manufacturers alone.

Projects that still need direct PLC connectivity require a device connectivity product. The OPC NEXUS guide covers that broader selection.

Key Specifications of UaGateway

Supported Servers and Connection Targets

UaGateway connects to existing OPC servers and exposes their information through its own server interfaces. The required configuration depends on each application's role as a client or server and the data it exchanges.

Some source information has mapping limits. The version 1.7.3 documentation states that vendor-specific COM DA properties are not passed through to OPC UA. It also states that historical access exposes raw data, without the aggregates provided by underlying COM HDA servers. Applications using either need a compatibility test.

Supported Functions and Optional Add-ons

The base Data Access feature provides browsing, reading, writing and monitoring. Separate feature keys enable the following functions:

• Alarms and Events adds mapping between Classic OPC A&E and OPC UA alarm/event interfaces.
• Historical Data Access adds historical read access between OPC HDA and OPC UA.
• TagFile & Cache creates a configurable address space with mapped or internal cached variables.
• TagLinker copies values from configured source tags to target tags when values change.
• Store & Forward combines HDA and TagFile & Cache for local logging in a rotating database.

UaGateway also supports Reverse Connect, allowing a connection to be initiated from the protected network side. The deployment must permit the required outbound traffic.

Deployment Requirements and Licensing

UaGateway runs as a 32-bit Windows service and operates on 64-bit Windows through WOW64. Installation requires administrator rights. Confirm support for the intended Windows edition and build before deployment.

Unified Automation recommends placing UaGateway on the same computer as the Classic OPC COM client or server. Remote DCOM configuration is outside its support scope, and only one UaGateway installation can run on a PC.

Standard runtime licensing applies per installation. For a quotation, provide the deployment computers or virtual machines, connection topology and required features. Buyers in India should also confirm the purchasing route, support arrangements and maintenance terms.

UaGateway Case Study: Valio

Unified Automation's September 2012 case study describes UaGateway's use at Valio, a Finnish dairy processor.

Challenges Before Implementation

Valio needed to connect production data to MES and enterprise applications across automation systems from different vendors. Classic OPC was already established at production level, but communication across network boundaries created administration and security problems.

Implementation and Reported Results

After prototype testing, Valio selected UaGateway for its OPC UA integration backbone. Prosys connected legacy OPC servers with UA clients while retaining existing production communication and network infrastructure. Following this work, Valio decided to extend OPC UA integration gradually across 15 production sites.

Lessons for Projects in India

The Valio approach offers a starting point for an Indian plant with established OPC systems: map the production-to-MES data path, identify the network boundaries, and test a representative connection before expanding. The case demonstrates a migration approach; it does not document an Indian deployment.

Is a UaGateway Trial or Demo Available?

Unified Automation offers an evaluation download with a one-hour runtime limit; the software can be restarted. Registration and login are required. This runtime limit is separate from the manufacturer's general evaluation licence period.

Test browsing and any required writes, along with values, timestamps and quality information. Include connection loss and recovery, plus alarm or history behaviour where needed. For longer uninterrupted acceptance testing, discuss evaluation terms with Unified Automation.

Manufacturer Information

Unified Automation GmbH supplies OPC UA software, development tools and runtime products. The OPC Foundation lists it as a Corporate Member.