The future development direction of programmable PLC controller

Date:2022-06-02 09:26

In the future, programmable PLC controllers (PLCs) will continue to advance in the fields of hardware, software and communication to adapt to the development of science and technology. Possible evolutions will include a combination of PLC and programmable automatic controller (PAC) functions to enable communication from the bottom to the top of the factory.


From the beginning, when PLCs began to replace relays and timers in large numbers, there was a driving force to reduce the size of automatic control systems and simplify support and maintenance for future trends in PLCs. Over the past few years, relays have been replaced by smaller rack-based architectures or smaller programmable logic controllers with remote input/output ports.


With the development of microelectronic technologies such as ultra-large-scale integrated circuits and ultra-large-scale integrated circuits, programmable logic controllers have developed from the initial unit computer to the current microcomputer PC composed of 16-bit and 32-bit microprocessors, realizing multi-channel processing of multi-processors. Nowadays, PLC technology is very mature, not only enhance the control function, reduce power consumption and volume, reduce the cost, improve reliability, make programming and fault detection more flexible and convenient, but also with the development of remote I/O and communication networks, data processing and image display, PLC towards the direction of continuous production process control, become the pillar of industrial production automation.


With the increasing application of programmable controllers, programmable controller technology and its product structure are also constantly improving, more and more powerful, and the cost performance is getting higher and higher.


1. Smaller, faster and better

As the electronics industry continues to evolve, the size of today's processors, circuit boards and components continues to shrink. These technologies are slowly taking effect on PLCs, making them more stable, reliable and robust, and further refining their features such as faster processors, scalable memory capacity, and new featured communication mechanisms.


In response to market demand, many features and functions are shifting from high-end PLCs to low-end PLCs. For example, we can expect that future small PLCs will have more high-end PLC functions, while mid-to-high-end PLCs will also provide smaller, more compact solutions to meet customer needs.


At the same time, PLCs also benefit from reduced memory costs and volume. These benefits greatly increase the storage capacity of localized data and allow programmable logic controllers to be used in applications that used to require expensive data capture systems. This also enables the implementation of other functions, such as on-board storage of product information, to speed up troubleshooting.


Today's PLCs also benefit greatly from USB technology, which makes networking, programming and monitoring control systems easier than ever. With the continuous advancement of USB technology and the advent of smaller mini USB connectors, you can expect to see this communication option on more small PLCs.


Another example is the non-volatile portable memory device, which has rapidly penetrated the industrial market from the rapidly changing world of consumer electronics. By providing a lot of extra storage space in a small package, they bring great benefits to PLC users. These possible options include USB devices, SD cards, mini SD cards, micro SD cards, etc. , adding up to 32GB of additional storage for end users, machine builders, and system integrators.


2. Integration of programmable controller and polyaluminum chloride

Many industrial controller vendors still sell the similarities and differences between PACs and PLCs, but future automation engineers may not care what the name is when considering their systems, but only focus on performance and actual functionality. Just as the definitions and characteristics of these two devices are constantly evolving, PLC and PAC will also evolve with each other.


Based on this evolution, there will be plenty of opportunities in the low-end and high-end markets. As hardware technology advances, advanced features will find their way into low-end processors. This, in turn, will push vendors to integrate more features and options into high-end products.


High-speed processors and larger storage spaces will facilitate the application of advanced functions such as motion control, vision system integration, and collaborative support of various communication protocols. Of course, in order to attract more users, PLC will still retain its simple functions.


In the process of PAC and PLC integration, we can see that these two products are constantly improving and progressing. PAC allows users to expand into the traditional field of industrial automation, encouraging suppliers to develop new products that meet customer needs.


These requirements challenge product designers: forcing them to look for new directions, such as supporting existing components to build new systems that meet harsh industrial environments. Future challenges will include providing connectivity, expanding storage capacity, and increasing controller processing power to handle increasingly complex applications while maintaining or even reducing the cost of the end product.


3. Ladder language: Never say goodbye

Fifty years ago, hard-wire relay logic was replaced by ladder language, bringing convenience to technicians and engineers familiar with relay logic, but with its limitations, especially in process control and data processing applications.


IEC61131-3 provides another programming language for industrial controllers, but ladder language still has its own advantages and has always shown its unique charm. Although process control has a continuous function diagram, structured text is also good for data processing, and other IEC languages have their own advantages. But ladder languages will remain the leader of PLC programming languages.


Suppliers and their customers purchase PLCs with logic programming in the ladder language and use these PLCs to control a large number of basic devices. There are also a large number of engineers, technicians, electrical engineers and maintenance workers who prefer the simple programming technique of ladder language. No matter how hardware evolves, this language will continue to be the industry standard for PLCs for a long time to come.


While ladder logic languages can serve as the cornerstone of simple machine control, function block programming techniques can reduce the amount of code, especially when PLC code needs to be integrated into a unified programming environment.


4. Unified programming environment

Combining programmable controllers, motion control, and HMI programming into a unified environment is a trend in the coming years. Integrating programmable controllers and HMIs in the same rack could be the next trend, regardless of whether the display is included in a component or as an external option. Whether it is the same processor or HMI module integrated into the PLC I/O rack, current technology can support both configurations.


A unique programming environment is ideal for most users, as long as it is not too complex. The advantages of combining these modules include shorter learning cycles and development times. However, if this programming environment is not well designed, it can become cumbersome and difficult to operate.


An important step in having a unified programming environment is to ensure that devices can share the same tag name database. Labels are an important link between procedures and procedures. Setting up a database is a time-consuming project, and reducing these repetitive tasks will shorten overall R&D time and reduce the probability of errors.


5. Welcome to the wireless era

Over the past few decades, especially in the early 90s of the 20th century, a large number of different communication networks and protocols have emerged in industrial applications. Over time, these different choices were left to a small number of leaders. As with consumer PCs and their peripherals, this trend will continue, with a focus on self-configuring plug-and-play solutions in the future.


In fact, whether these communication technologies can achieve real-time performance does not need to be a concern, because the original speed of many industrial control networks, such as Ethernet, is much faster than the needs of most applications.


As for the common interface between local storage devices and other devices, while USB is available, it also has its limitations. USB is plug-and-play, but integrating hardware and software with USB requires additional investment from the device vendor. Because of this, industrial hardware suppliers such as barcode readers and electronic scales are changing slowly, and RS232 interfaces will still be used in the short term.


At present, the communication interface of high-end PLC can adapt to a variety of protocols. It is expected that this situation is expected to improve as user needs are standardized in the future, perhaps only in Ethernet and wireless forms, or there are possible options for industrial Bluetooth.


This is a wireless era. However, before we see a huge convergence of commercial and industrial wireless communication protocols, industrial applications do require wireless technologies that are robust on a larger scale and ensure data integrity.


In this space, we're also seeing progress: from the latest Wi-Fi (802.11n) and ZigBee (802.15.4) protocols to the rise of point-to-point connectivity, mesh connectivity, and Bluetooth and near-field communications, but these are not yet factory-level solutions suitable for mission-critical tasks. In the future, wireless technology will be more widely used in RTUs suitable for wireless applications or some non-critical monitoring applications that do not require real-time control.


6. Fully integrated factory

The most striking change in PLC in the future should be the integration of enterprise resource planning (ERP) systems or other advanced systems with the plant level. In the past, the main integration task was to extract machines and process data and upload it to those advanced systems. In the future, new technologies such as hooks and functions will simplify this integration.


In view of this, controller manufacturers need to consider the needs of users more when designing PLC solutions. The solution is not only used for control, but also enables seamless operation, providing data to the users who need it. This may include providing access to data available through a browser or mobile application, or including tools to access databases.


Enhanced communication, increased processing speeds, and greater storage capacity give PLCs the ability to manage the data they generate. This is a natural trend for PLCs.


While form, usage, and performance will change considerably, in the future, the term programmable controller will continue to serve as the name for many industrial automation controllers. The scale of PLCs will continue to shrink, and the development of hardware will also bring new features and functions to PLCs. The improvement of software and communication capabilities will give the long-standing name PLC a new positioning - industrial automation platform.