OPC UA with Peakboard: Read Machine Data Directly from the PLC
What OPC UA is, how the communication standard works and how Peakboard builds an OPC UA connection to the machine controller in a few steps, without programming.
02.07.2026
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6 min read
- OPC UA (OPC Unified Architecture) is the industry standard for communication between machine controllers and higher-level systems.
- An OPC UA server provides data points in a node structure – Peakboard subscribes to the relevant values directly, without middleware.
- The connection in Peakboard Designer is set up by configuration – no code, no driver, no additional tool.
- OPC UA supports different security levels: anonymous, certificate-based, encrypted.
Peakboard connects directly to the OPC UA server of a machine or PLC, subscribes to the relevant data points and brings machine data into the dashboard in real time with no detour – no middleware server, no additional driver, no programming. This article explains what OPC UA is, how the connection is built in Peakboard and what to watch out for when getting started.
What is OPC UA?
OPC UA stands for OPC Unified Architecture. It is the most important open communication standard for industrial automation systems. OPC UA enables platform-independent, secure data exchange between machine controllers (PLCs), field devices, MES systems and visualization solutions like Peakboard.
Unlike older standards such as OPC DA, OPC UA is not restricted to Windows and runs equally on embedded systems, Linux servers and Windows. Most modern PLC manufacturers support OPC UA natively: Siemens S7-1200/1500, Beckhoff TwinCAT, Allen-Bradley, ABB, KUKA and many more.
How does OPC UA work?
OPC UA is based on a client-server model. The OPC UA server runs directly on the machine controller or PLC and provides data points – in OPC UA terms: nodes – in a hierarchical structure. An OPC UA client like Peakboard connects to this server, navigates through the node structure and subscribes to the desired values.
Three concepts matter when getting started:
- Nodes: data points in the node structure, for example
Machine1/Status,Machine1/CycleTime,Machine1/FaultMessage. Every node has a unique NodeID. - Subscriptions: Peakboard subscribes to nodes and automatically receives updates when a value changes – no cyclic polling required.
- Endpoints: every OPC UA server offers connection endpoints with different security levels – anonymous, signed, or signed and encrypted.
Configuring OPC UA in Peakboard
The OPC UA data source is configured in Peakboard Designer without programming. The essential steps:
- Create a new OPC UA data source and enter the server URL. Format:
opc.tcp://[IP address]:[port], for exampleopc.tcp://192.168.1.10:4840. - Select the endpoint: Peakboard lists all available endpoints of the server. For getting started, “None” (no security profile) is often enough. In production, at least “Sign” should be used.
- Certificate: even with anonymous access, Peakboard needs a client certificate for identification. In the Designer this certificate can be created directly in a few clicks.
- Test the connection: a click on “Connect” checks the connection. On success, the subscriptions dialog opens with the complete node structure of the server.
- Select nodes: in the node structure, select the relevant data points and add them to the subscription. Peakboard shows the values live immediately.
What comes after the connection?
As soon as OPC UA data flows into Peakboard, all standard functions are available: data points can be bound directly to controls (text, traffic light, gauge, progress bar). Peakboard scripts can react to value changes – for example to trigger a message automatically on a fault code. State changes can be written to a SQL database via a stored procedure to build a data historian. And threshold violations can trigger an Andon signal.
OPC UA vs. S7 direct access
Besides OPC UA, Peakboard also supports direct S7 access to older Siemens controllers (S7-300, S7-400, S7-1200). The difference: OPC UA is the standardized, manufacturer-independent route and is supported by all modern controllers. Direct S7 access is the solution for legacy equipment where no OPC UA server is available or configured. Both connection types can be used in parallel in one Peakboard project.
From the OPC UA signal to the Andon board
The most common first use case after an OPC UA connection: making machine status visible in real time on the shop floor. Peakboard subscribes to the machine's status node – RUN, STOP, SETUP, FAULT – and shows it immediately on an Andon board. No delay, no manual entry, no middleware. When several machines are connected via OPC UA, a line overview emerges from it automatically – the first step to full machine monitoring.
Data connection
OPC UA with Peakboard
How Peakboard configures OPC UA connections, which security levels are supported and which machines can be connected directly.
What is OPC UA?
OPC UA (OPC Unified Architecture) is a platform-independent communication standard for industrial automation systems. It enables secure, manufacturer-independent data exchange between machines, PLCs and higher-level systems like Peakboard.
Which machines support OPC UA?
Most modern machines and PLCs support OPC UA natively: Siemens S7-1200 and S7-1500, Beckhoff TwinCAT, Allen-Bradley CompactLogix, KUKA robots and many more manufacturers.
Do I need an additional server for OPC UA with Peakboard?
No. Peakboard connects directly to the OPC UA server of the machine or controller. No middleware server, no KEPServerEX or similar additional tool required.
What is the difference between OPC UA and the old OPC DA?
OPC DA was Windows-only and relied on DCOM, which made network configuration error-prone. OPC UA is platform-independent, runs on Linux and embedded systems, supports encryption natively and is the current industry standard.
How are security certificates managed with OPC UA in Peakboard?
Peakboard Designer creates client certificates directly at a click. The certificate then has to be marked as trusted on the OPC UA server – a one-time step, after which the connection runs automatically.
What is the difference between OPC UA and S7 direct access in Peakboard?
OPC UA is the standardized route and is supported by all modern controllers. S7 direct access is the solution for older Siemens controllers without an OPC UA server. Both can be used in parallel in one Peakboard project.
