OPC Unified Architecture (UA)

The inclusion of cloud services in the automation process is becoming increasingly attractive, whether for the implementation of central data storage or even for analysis purposes. By extending OPC UA with publisher/subscriber mechanisms, such cloud services can be connected, e.g. via the MQTT transport protocol. With the products TF6105 TwinCAT 3 OPC UA Pub/Sub and TF6720 TwinCAT 3 IoT Data Agent, Beckhoff provides two TwinCAT 3 functions to address such application scenarios. In addition, the IoT bus coupler EK9160 enables direct connection of the I/O level to the cloud via MQTT.

With the functions TE6100 TwinCAT 3 OPC UA Nodeset Editor and TF6100 TwinCAT 3 OPC UA, Beckhoff enables the integration of companion specifications into the automation project as well as their subsequent use. The Nodeset Editor can be used to load companion specifications (or the resulting nodeset files) and use them for modeling the machine project. Data points from the companion specification can be graphically linked to data points from the PLC. Automatic PLC code generation reduces the engineering effort and makes integration easier. The resulting project can then be loaded into the TwinCAT OPC UA server, providing OPC UA clients with a standardized interface for accessing machine data based on the companion specification.

The TwinCAT 3 Scope is a software oscilloscope for the graphic representation of signal curves in different chart types. These could be, for example, YT, XY, bar or digital charts. Long-term recordings, advanced export options and trigger-controlled storage are included in the range of functions. Through the integration of OPC UA, TwinCAT Scope also enables access to variables from third-party devices, allowing them to be diagnosed easily and conveniently in the familiar Scope interface.

OPC UA can also be integrated into the TwinCAT HMI. This enables the visualization of third-party devices and access to the variables provided there.

The Beckhoff Device Manager can be used to perform device diagnostics with a multitude of system values and is pre-installed in all Beckhoff Industrial PCs as standard. The system values can be accessed via standard functions of the Windows operating system and via special functions of the Beckhoff BIOS. Because the control computer is the central element of the machine control system, any failure can cause high downtime costs. It is therefore essential to be able to check the device. To prevent failure and minimize downtime, it is important to detect critical conditions early on. These include impending heat collapse due to failure of a fan or insufficient passive cooling. For the acquisition, analysis, and evaluation of system data during operation, all Beckhoff IPCs therefore offer the option of sophisticated system diagnostics with standardized, safe access to existing hardware and software components. The Beckhoff Device Manager has an integrated OPC UA Server that is ready to use on every Beckhoff Industrial and Embedded PC and offers access to the diagnostics data of the IPC.

Thanks to TwinCAT's open and flexible communication architecture, the TwinCAT 3 functions are also ideal for implementing retrofit scenarios. An existing machine can be extended very easily via a Beckhoff edge device with OPC UA technology without having to change the machine's program code. When selecting the edge device hardware, the customer can draw on the wide variety of Beckhoff industrial PCs. In principle, every Beckhoff industrial PC is capable of providing and executing such edge device functionalities. This allows you to scale the edge device and the software running on it perfectly for its intended use.

Modularity is an important topic in mechanical and especially plant engineering in order to increase the flexibility and reusability of plant components. This minimizes changeover and setup times. Module Type Package (MTP) has been established as a standard across manufacturers and communicates with OPC UA during productive operation. TwinCAT supports effective plant module creation in the engineering and production phases using the TwinCAT 3 functions TF8400 and TF8401.

In the classic system architecture, I/O devices, e.g. EL terminals, are connected in TwinCAT and processed and switched there accordingly. In this way, the function TF6100 TwinCAT 3 OPC UA can be used to make the I/O devices accessible via OPC UA.

However, the IoT coupler EK9160 also provides a hardware bus coupler that has an OPC UA server interface directly integrated. The connected I/O terminals are automatically detected when the device is started and made available via the OPC UA server. This enables fast and secure connection of I/O data points. The EK9160 can also demonstrate its strengths in retrofit scenarios: Additional sensors can also be added to an existing plant without much effort and made available via the standardized OPC UA interface.