Litmus has launched Litmus OPC Fusion, a free Windows-based bridge that pulls data out of legacy OPC DA ("Classic") servers and republishes it as OPC UA, without any changes to the underlying servers. The company describes it as a way to "unlock your trapped OPC DA data" for plants still running equipment tied to the decades-old protocol.
OPC DA runs on Windows COM/DCOM, a design that makes remote and secure access difficult and keeps that data cut off from modern OT-IT pipelines. Ripping out working OPC DA infrastructure carries real risk on a production floor, so plants often leave it alone and accept the resulting blind spot in analytics and AI models. OPC Fusion is built to close that gap by sitting alongside existing OPC DA servers, reading their tags, and exposing them through a standard OPC UA endpoint that any compliant client can consume.
The tool supports bidirectional conversion, reading OPC DA data out as OPC UA and writing OPC UA values back down to OPC DA, and Litmus says it's validated for high-density tag environments. It also connects to OPC DA servers on other machines across the network, a feature Litmus notes that "many alternative converters advise against." Compatibility spans Windows XP SP3 through Windows 11 and Windows Server 2025, in both 32-bit and 64-bit builds, with configuration and monitoring handled through a browser-based interface. Security options include OPC UA Sign and SignAndEncrypt modes, certificate management, and a trust-list workflow for client connections.
Engineers running legacy gauging, SPC, or process-monitoring systems on OPC DA will care about the remote-connectivity piece specifically, since it removes one of the more common excuses for leaving that data disconnected from cloud or AI tooling.
OPC Fusion's primary role is to feed Litmus Edge, where the converted data joins the Litmus Industrial Data Foundation for tag contextualization, edge analytics, and Edge AI, then routes northbound to AWS, Azure, or GCP or into a Unified Namespace. That distinguishes it from a standalone DA-to-UA point converter, which stops at protocol translation.
The tool is available now through the Litmus Central Portal at no cost, and Litmus says it's backed by the company's standard release cycle, support SLA, and bug-fix commitments rather than treated as a side project. Setup and tag-mapping documentation is published separately at docs.litmus.io.
