Mr. Vögel, virtual control is currently a hype topic. You now also offer Codesys as such a virtual controller. How realistic are applications today in which your users control their machines from the cloud?

First of all, it depends on the definition of the cloud. If it is a server farm in the classic sense, located several hundred kilometers away and connected via the Internet, then it is of course difficult to control applications in real time. Ultimately, Codesys is also subject to the laws of physics, and the resulting latencies would simply be too great. Nevertheless, such a cloud is suitable for applications in the field of building automation or process automation, for example, as the focus here is usually on high availability and redundancy rather than low latency.
If we look at the factory environment, it is now often the case in larger companies that their own server networks form a 'private cloud'. This type of infrastructure is ideal for hosting the Codesys Automation Server on-premises, for example - or for centralized control of machines at your own site using a virtual PLC.

Your highlight at the trade fair is the virtual safety controller. To what extent is this already a reality or still a vision?

Anyone can see for themselves here at the fair! We have a prototype of our Virtual Safe Control at the trade fair and invite everyone to come and see for themselves.
The concept has already been approved by TÜV. We are planning an initial release in the second quarter of 2024, so the virtual safe control system is beyond the vision stage, although there is still a lot to do.

With virtual control systems, the hardware is completely abstracted. In order to achieve dual-channel capability, there is no need to rely on additional hardware. You say that you can still create a two-channel system using software with diversified encoding. Won't this cause performance problems?

The concept of diversified encoding has been around for many years. In fact, just a few years ago it was hardly practicable because the necessary processes simply took too long. In the recent past, however, the underlying algorithms have been significantly improved. In addition, there has been a veritable explosion in the performance of available hardware. The combination of these factors means that we no longer see any problems in using this technology. For example, we are using standard Linux IPCs in our exhibition setup here at the SPS, and we see no problems with virtual safe control. To give a performance example: On an Intel i7, we achieve an execution time of a few milliseconds with 50 Profisafe connections.

Isn't I/O handling for safety applications difficult or time-consuming?

I/O handling for safety applications is basically exactly the same as for functional virtual control. This means that there can naturally be no local I/Os. Typically, an Ethernet port of the device used, whether IPC or server, is mapped into the container used. A network can then be set up from this port, which is used to control the desired modules. In contrast to a machine with a conventional, dedicated controller, the physical path that the network has to bridge is often longer, as the PLC is no longer located directly in the system's control cabinet. In order to bridge these longer distances, the network should be virtualized, using technologies such as vxLAN and PRP.

Codesys at the SPS 2023: Hall 7, Stand 677