Siemens Releases a New Virtual PLC, the S7-1500V
The SIMATIC S7-1500V is Siemens's newest PLC, but it looks completely different than any other PLC… Mainly because it doesn’t physically exist.
Virtual PLC
A PLC is simply some hardware components, similar to a computer that only runs one application whose purpose is to convert digital logic into real-time inputs and outputs that manipulate components in the real world. The biggest difference between the two is how programs run. A PLC scans inputs, runs logical algorithms, and then updates output terminals in sequential order. A PC can run multiple tasks at once with the use of multi-threading and time-splicing. So how could a PLC be virtual?
To answer this question, we need to look back to when PLCs were first being used.
Siemens’ new virtual PLC promises greater flexibility, security, and access to modern industrial automation. Image used courtesy of Siemens
The History of PLCs
PLCs were first used in the late 1960s and were pioneered by General Motors. At the time, computers were not commercially available and were very expensive. Now, fast forward to today; most of us have enough computing power on our cell phones to automate an entire assembly line! Since a PLC stores memory and computes logic just like a computer, virtualizing a PLC on today’s computers makes perfect sense.
Simulating a PLC
Most PLC software today has a method of simulating the controller. While simulation functionality does help troubleshoot programming and logic issues, the software is not capable of monitoring and controlling real-world I/O locally or over a network; it is only what it claims to be: a simulation of real-world events.
Siemens’ SIMATIC S7-1500V
Recently, Siemens has released their own soft PLC or virtual PLC, the S7-1500V. This controller is entirely virtual and can be installed on most industrial-grade servers or PCs. The controller is integrated into both TIA Portal, the Siemens PLC and automation software, as well as the Industrial Edge computational platform. The S7-1500V offers mobile device support along with multiple instance flexibility.
One of the primary benefits of the PLC system is the programming environment designed by industry professionals, for industry professionals. With the 1500V being integrated into TIA Portal, technicians and engineers alike can use familiar programming tools or even convert existing projects to use the virtual PLC.
Engineers familiar with the TIA portal IDE will be better equipped to deploy the S7-1500V platform. Image used courtesy of Siemens
Instead of purchasing a new PLC, the 1500V can be installed on existing IT equipment or equipment that is no longer in service. With servers having better security features installing the S7-1500V allows for easier remote access to the PLC.
Interaction with all real-world devices is still obviously necessary for function. Much like a modern PLC, the virtual platforms allow network ports to be configured for communication among a virtually endless combination of distributed I/O devices, motor/motion controllers, and visualization (HMI) applications.
Previous Virtual PLCs
Virtual PLCs aren’t exactly a brand-new concept. Other companies have developed basic systems in the past, with software that would connect to industrial networks and could control field I/O devices, but these have typically been limited to only motion, and many industrial networks were left unsupported in favor of proprietary systems.
A major problem with this option was the cost. High-end computers used to cost nearly as much as PLCs, so it didn’t make much sense to purchase a dedicated PC if you could purchase a PLC for the same amount. However, with PC technology advancing faster than PLCs, the cost differential is reducing to bring more economic value to virtual PLCs, which might possibly be making a comeback.
The S7-1500V combines the familiarity of the S7 PLC series with the flexibility of modern PC computing. Image used courtesy of Siemens
Moving To A Digital World
The automation world is becoming more and more virtual every day with digital twins and simulation software, it won’t be long before the entire automation line is running off a computer. The advantage of using a virtual PLC is reliability and speed.
Currently, there is a supply chain issue that is making it very hard to get automation components, no matter where you are located. The delivery time on some PLCs is nearly 300 business days. For machine builders, this presents a huge problem, but if we can run our PLC programs off a PC that can be delivered in as little as a single week, the problem is alleviated. Data collection on equipment is also becoming a popular trend, and with PLCs and PCs sharing similar components, it makes sense to have both systems on one piece of hardware.
Every manufacturer’s nightmare is a PLC failing during production. Some companies keep stock of spare parts, while others may not be able to afford to have PLCs sitting on a shelf. A virtual PLC can be installed on a business class server which has tools for data recovery and hardware failure.
Who knows, a virtual PLC might just be the best PLC controller for your next project.
I mean was these concepts utilized by siemens and RA few decades back. I still remember the softlogix RA had achieved this on windows platform with controlnet PCI cards running on industrial PC. Similarly Siemens also had WinAC RTX that ran on windows. Those days Virtualization was catching up. But this is not a new concept and also OEM’s like Honeywell had these few years before in the market in DCS like virtual UOC with full fledged redundancy and all. Seems like vendors need to catch up!