New trends in Programmable Logic Controller
A programmable logic controller (PLC) is an automated system that collects data from a variety of input devices, including sensors that monitor parameters such as storage tank levels, pressure, and temperature. Using programmed software logic, the PLC then processes the collected data, makes appropriate logic-based decisions, and sends issued instructions and commands to process and machine control. PLCs have been around for nearly 50 years and are still considered the best option for a wide range of industrial automation applications. Despite that era, PLC technology is evolving and PLCs are expected to maintain their dominance in the world of industrial automation for the next few years. Below are some of the 10 latest technological developments that have evolved and adapted PLC technology to the times.
1) Compact size, faster processing time, cost optimization
Technical improvements such as reduced size of processor, circuit board and other components. It's changing the electronics industry. In addition, these improvements are beginning to affect PLCs after the introduction of small micro and nano-class PLCs. These new PLCs are smaller, but with faster cycle times, larger memory capacity, new communication improvements, and faster processors.Prior to , the above features were only high-end and mid-range PLC features, but in response to market demand, many of the high-end features have been moved to low-end PLC systems. As a result, we have moved from a large PLC to a small PLC. This is because micro and nano classifier PLCs can also provide remote connectivity, Ethernet communication, onboard PID with auto-tuning, motion control, and other control functions.For example, PLC manufacturers are taking advantage of the dramatic reduction in size and cost of solid-state memory. This allowed for a significant increase in local data storage, allowing PLCs to be used in many applications that initially required expensive data acquisition systems. In addition, the reduced memory size allows for many other features such as on-board storage of product information and faster debugging of PLC control systems.In addition, current PLCs benefit from USB technology, making online programming and monitoring of control systems much easier. In addition, as USB technology continues to evolve with the availability of micro and small mini USB connectors, these communication options are expected to be incorporated into smaller PLCs.In addition to USB readers, the PLC also integrates with SD cards, micro SD and mini SD cards, and other small connected devices. These portable devices provide PLCs with up to 32GB of additional non-volatile storage, depending on the needs of system integrators, machine builders, or end users. This is a hallmark of the fast-paced consumer electronics industry, where integration with PLC is rapidly revolutionizing industrial control systems.
2) Enhanced Communication Networks
Over the past few decades, especially in the early 1990s, a wide variety of communication protocols and networks have been developed for use in industrial communications. This trend continues to focus on real-time communication technologies, raw Ethernet connection speeds, and other industrial control networks for a variety of applications. In their present form, high-end PLCs include multiple ports to support several communication protocols. But looking into the future, this is likely to change as users continue to demand more standardized Ethernet and Wireless communication options. Even though it’s a wireless age, industrial processes would require more robust wireless technologies with enhanced data integrity and improved communication range, before we can witness a convergence of industrial and commercial wireless communication protocols.Though there has been great progress in this field, from the latest ZigBee (802.15.4) and Wi-Fi (802.11n) protocols to the use of mesh and wireless ad hoc networks (WANET) as well as the rise of Near Field Communication (NFC) and Industrial Bluetooth; none of these wireless technologies has proven capabilities for mission-critical operations often encountered plant floors. Therefore, in the future, a great deal of less critical PLC controlled applications in which real-time control isn’t essential, are likely to widely adopt wireless communication networks particularly in RTUs (remote terminal units).
3) PAC (Programmable Automation Controller) and PLC Integration
In general, Programmable Automation Controllers (PACs) are an enhanced modular industry that uses PC-based processors to provide even more programming. It is a controller for. Option IEC61131-3 programming language. Also called an industrial PC or just IPCPACs are considered more advanced than PLCs. However, over the years, PLCs have evolved to adapt to improvements in hardware technology, software, and communications. High-end features are built into the low-end PLC processor.For example, with larger memory capacity and faster processors, we have the opportunity to integrate advanced features with PLCs such as: B. Motion control, simultaneous support for multiple communication protocols and high resolution image processing systems. On the other hand, despite its advanced features, the PAC system maintains the simplicity of appealing SPS to many end users. In addition, the capabilities of PAC allow users to push the boundaries of traditional industrial automation and product designers to create custom controllers to suit their needs.Throughout this evolution, many industrial control manufacturers have continued to promote the difference between PAC and PLC. However, at the same time in PLC and PAC, the definitions and characteristics of both classes changed, and much faster progress was seen in both classes. Therefore, as the two controllers evolve, the two functions will continue to be integrated. In fact, in the future, automation engineers may move away from nomenclature and focus on the features and performance available when specifying control systems.
4) Open Source PLC
When you come across the term "open source", you think of an open source hardware design, or a standardized, non-exclusive PLC scripting language implemented under a public license. However, the impact of the open source era on the PLC industry is very comprehensive.PLC technology completely eliminates the concept of PLC by suggesting that it should be based on a computer system such as the Raspberry Pi. More and more companies are adopting Raspberry Pi and incorporating it into systems that are robust and can withstand the extreme environments of industrial applications. In this case, the Raspberry Pi is typically paired with one or more boards that provide the digital / analog and I / O capabilities that make up a traditional PLC.With Raspberry Pi, the additional circuit boards are designed with the capability to withstand high currents and voltages and to provide the isolation required in an industrial environment. Therefore, in terms of hardware, the Raspberry Pi can at least be integrated into industrial automation through such extensions.In terms of software, single-board computers such as Raspberry Pi are not designed to be programmed with IEC 61131-3 standard languages like Function Block Diagram or Ladder Logic used to program PLCs. Instead, Raspberry Pi runs on an operating system like Linux or a derivative of Linux, and such an O/S is best accessed by high-level programming languages including Java, C and C++, and other higher levels of abstraction which purely use mathematical expressions. This is quite different from the bit-bashing environment of Microcontrollers Units (MCUs), that support Ladder Diagram and other IEC languages.However, some companies like Phoenix Contact are taking advantage of the open-source disruptions in the PLC market, to create open programming platforms like “PLCnext”. "PLCnext" is an open programming environment based on Linux O / S, but intended for PLC applications. This is achieved by using high-level IT technologies such as HTML or by giving system designers the option to configure the control system based on the IEC 61131-3 programming language.
5) PLCs Design designed for Industry 4.0 Many technological innovations such as artificial intelligence, cloud computing, advanced sensors, and big data analytics are having a major impact on the manufacturing situation. These advances in industrial technology are commonly referred to as Industry 4.0. In the reality of this new industry, PLCs continue to play an important role as main controllers, input hubs, and interfaces for human operators.To continue to be the central processing unit for real-time manufacturing operations, PLC technology has been further developed to enable better communication with multiple input sensors over the Industrial Internet of Things (IIoT). This makes it much easier for SPS to capture large amounts of data and deliver it to machine learning programs.For example, data from input sensors and other devices can be integrated with PLC data to give a “big picture” of the collection of “big data”.Operations managers and data analysts use analytics tools to better track big data, leverage resources, perform logistics, plan orders, plan tasks such as timing suppliers. , You can create a very efficient manufacturing process. In addition, "big data" can be tracked and analyzed for optimal performance and preventative maintenance of machines and appliances in manufacturing systems.
6) Integrated programming environment
We tend to combine human-machine interface (HMI), motion control, and PLC into an integrated programming environment. This trend may continue for the next few years. This is followed by integrating the PLC with the HMI processor on the same rack and including the monitor as part of an external option or package. This technology allows the configuration of either HMI modules or HMI processors with PLC I / O racks.A non-overwhelming integrated programming environment is ideal for most system designers and control engineers. The main benefits of combining these modules include an overall reduction in program development time and a reduction in the learning curve. However, to get the most out of such tools, you need to think properly to make them easier to navigate.
7) More powerful and broader data exchange The PLC is more powerful and can be equipped with features previously reserved exclusively for workstations and PCs. This makes exchanging data from the PLC on the factory floor to a human operator in the control plane faster and cheaper. Features that allow current SPS to share data widely include internal relational databases, FTP servers, web servers, and sending email. Theweb server allows a PLC to host a website, for example, on the Internet or on the corporate intranet. The web server then provides access to real-time data logging and acts as a backup HMI for your work cell or machine.In addition, the web server feature can store documents on some PLCs, allowing you to view machine schematics and drawings, as well as operation and maintenance manuals with short video clips. As a result, PLC web capabilities vary from model and manufacturer design specifications, from a single "off-the-shelf" web page to a full-fledged site that uses JAVA and XML-based technologies. PLC web servers are probably the most popular of PLC's new data sharing technologies.In addition to the PLC web server, there is a Send-Email feature that simplifies and automates the export of critical and production data from the PLC to human operators. This allows the PLC control program to output production data, status changes, material consumption reports, alarms, and PLC internal data. Interestingly, the PLC's email sending feature allows you to quickly send alarm messages to maintenance personnel via your mobile phone or alphanum pager.
8) Advances in Ladder Logic
50 years ago, Ladder Diagram (LD) replaced hardwired relay logic as a PLC programming language. The LD language kept things simple for system engineers and designers accustomed to passing logic, but at the time there were some limitations, especially when it came to data processing and process control.Other PLC programming languages such as function block diagrams (FBD), structured texts (STX), sequential function charts (SFC), and instruction lists (IL) are introduced in IEC61131 to address the challenges of ladder diagrams. It was-3.3. However, the developers of ladder diagrams have responded to that advance. This surprisingly remains relevant and powerful in industrial control programming. All IEC languages have advantages because STX is suitable for data manipulation. However, ladder logic is still on the rise and continues to be the overwhelming leader in PLC programming languages.For example, control system vendors and end users support large-scale base installations of devices, machines, and processes controlled by ladder logic PLCs. There is also a large group of maintenance personnel, electricians, technicians, and engineers who prefer the simplicity of ladder logic programming technology. In addition, regardless of the hardware used, the LD language has come a long way in creating industry standards for PLC programming. This trend may continue for the next few years.
9) PLC Designs that Withstand Harsh Conditions
PLCs that are currently available in the market are rugged and designed to withstand extreme climatic events like cold snaps, floods, or heat waves; conditions that could potentially damage electronic devices including PLCs. These robust and sturdy PLCs designs are being made with more durable materials like fiber signals instead of electronic signals, making them well-suited for some electronically hostile plant floors. In addition, due to the advancements in IIoT technology (previously discussed), PLCs can now be housed in isolation of harsh environmental conditions and operated remotely from regions with less or zero electrical noise disruptions. This has proven to be of great benefit whenever there are sensitive processes and sensors which require precise actions and monitoring
.10) Higher Security
Cybersecurity is becoming increasingly essential with the rise of interconnected devices in this era of the Internet of Things. For instance, interfering with the visibility of sensor systems or shutting down sensors, could cause work sites and plants to shut down; resulting in enormous losses. To contain or prevent this from happening, industrial control manufacturers are responding by incorporating the latest safety enhancements into their PLCs. For example, Honeywell Process Solutions (HPS) released the Control edge programmable logic controller in 2016. This PLC has a built-in cyber security function to prevent cyber attacks. In addition, Honeywell's next-generation controller leverages the power of the Industrial Internet of Things (IIoT).