How a PC-based control system is an option for every application
Controller specification is the most important stage of the development process for every industrial automation application. Historically, certain controllers were the de facto choice for a particular machine design, whether it was a programmable logic controller (PLC) or programmable automation controller (PAC) depending on the area and application.
These devices have performed adequately over the years and have fostered an "if it’s not broken, don’t fix it" mentality. However, as advances in automation technology continue to accelerate, PC-based control offers a unique set of opportunities covering a wide range of application areas and is becoming a controller of choice regardless of the application.
PC-based control system benefits
The biggest benefit of choosing a PC-based control system comes in the form of superior scalability in hardware and software. This offers engineers a clear and efficient migration path as machine and plant designs change over time. For example, some manufacturers offer a range of controller options from an entry-level to an advanced reduced instruction set computer (RISC) machines (ARM) processor, to a range of multi-core controllers in multiple hardware formats, up to an industrial server equipped with a 36-core processor that enables many-core control.
These all run PC-based control software for a range of functions, including PLC, motion control, safety, human-machine interface (HMI), measurement, condition monitoring, and others—typically all on one device in the case of multi-core controllers. Additionally, all but the multi-core performance end of the product range can be specified in multiple forms, whether it is DIN rail-mounted, cabinet-mounted, or integrated with an HMI screen, among other options.
HMI integration into an all-in-one device differentiates itself over a PLC or PAC for PC-based control options, as devices that integrate a screen for visualization are few. Solid-state storage options in the form of CFast cards (also known as CompactFast) and solid-state disks (SSDs) are also standard, reducing the number of moving parts and assuring high reliability for critical applications. As an operation grows and process needs rise, PC-based controllers easily can be swapped for a more powerful model that uses the same software platform. This exchange typically entails a simple exchange of a compact flash card from the old unit with the new controller and a system restart. Little or no programming is required (unless new functions are added), a benefit of a software-based automation system.
Using automation software to handle the controls-specific tasks and running it on multipurpose, PC-based hardware has become a game-changer for companies that seek a robust, flexible, easy-to-use development environment and control platform. For example, manufacturers offer control software that matches the PC-based hardware with different performance levels to meet the individual needs of each application, whether special features are called for in computer numerical control (CNC) motion and robotic kinematics or for PLC functions.
In addition, the automation engineering environment is built into Microsoft Visual Studio, making the software very familiar to the vast majority of programmers and allowing for programming work to be shared among engineers from various disciplines, such as traditional PLC programmers, computer science programmers, and information technology (IT) specialists. Reusing codes is a must and is something that control engineers must consider when selecting a new control platform. Function blocks in IEC-61131-3 programming languages or other object-oriented programming often are available in application-specific libraries. Reusing code facilitates a much shorter time to market and more flexible machine designs for original equipment manufacturers (OEMs), system integrators, and end users.
PC-based control platforms for IIoT implementation
Innovative engineers and company executives are quickly determining that the implementation of Industrial Internet of Things (IIoT) and Industrie 4.0 concepts is a logical next step to establishing more connected enterprises and is a necessary consideration for future updates and development. With a PLC or other closed hardware, adding IoT communication becomes a more difficult proposition and typically requires the addition of third-party hardware and software from IT companies to make everything work.
With PC-based control, this type of connectivity was possible before most major buzzwords of today were coined. More importantly, connectivity can be accomplished with little or no additional hardware because Internet and Ethernet connectivity has been built into PC-based control platforms for decades. Even if an operation isn’t quite ready to make the jump into the waters of IIoT and Industrie 4.0, PC-based control provides the most logical control platform with an unobstructed migration path to add higher levels of connectivity today or at any time in the future.
The already high demands for control systems will increase. As plant engineers and machine builders ask controls vendors to provide more functionality and connectivity within a comparable price point, flexible and scalable PC-based control systems represent the most cost-effective and robust option.
Eric Reiner is an industrial PC market specialist at Beckhoff Automation. Edited by Emily Guenther, associate content manager, CFE Media, Control Engineering, email@example.com.
- The benefits of a PC-based control system.
- PC-based control systems for IIoT and Industrie 4.0.
- How PC-based control systems fit for every application.
What are the pitfalls to using PC-based control systems?