As a PLC professional technician, I have witnessed the evolution of programmable controllers over the years. From their humble beginnings as simple relay replacements to their current status as advanced industrial automation tools, the development process of programmable controllers has been a remarkable journey. In this article, I will take you through the various stages of development that have shaped the modern PLC into what it is today.
The concept of a programmable controller was first introduced in the late 1960s by Dick Morley, who wanted to create a device that could control machines on the factory floor. In 1968, he developed the first PLC, called the Modicon 084, which was a large and expensive device that used magnetic core memory to store programs. This initial version of the PLC was not widely adopted due to its high cost and limited memory capacity.
However, in the 1970s, the development of microprocessors brought about a significant change in the PLC industry. The introduction of the microprocessor-based PLCs, such as the Allen-Bradley PLC-5, allowed for smaller and more affordable devices, making them more accessible to a wider range of industries. These PLCs also had a larger memory capacity and were more flexible in their programming, which opened up new possibilities for automation.
The 1980s saw a rapid growth in the use of PLCs in industrial applications. This was due to the increased processing power and memory capacity of microprocessors, allowing for more complex and sophisticated control systems. Additionally, PLC manufacturers started to incorporate advanced features such as PID control, data logging, and communication capabilities into their devices, making them even more versatile and efficient.
In the 1990s, the development of graphical programming software, such as ladder logic and function block diagrams, made PLC programming more user-friendly and accessible to individuals without extensive coding knowledge. This further increased the adoption of PLCs in various industries, including manufacturing, oil and gas, and transportation.
With the advancement of technology in the new millennium, there has been a shift towards more advanced and integrated systems. The traditional PLCs, which were standalone devices, are now being replaced by programmable automation controllers (PACs), which combine the capabilities of PLCs with those of industrial computers. This integration allows for better data collection, analysis, and control, paving the way for smart factories and Industry 4.0.
In recent years, the development of PLCs has also focused on increasing their connectivity and compatibility with other devices. With the rise of the Internet of Things (IoT), PLCs can now communicate with other devices and systems, such as sensors, robots, and enterprise software, to create a more interconnected and efficient industrial process. This has further revolutionized the role of PLCs in industrial automation.
The future of PLCs is exciting, with developments in areas such as artificial intelligence, machine learning, and cloud computing. These technologies have the potential to enhance the capabilities of PLCs even further, making them indispensable tools in the ever-evolving industrial landscape.
In conclusion, the development process of programmable controllers has been a continuous journey of innovation and adaptation. From their inception as basic relay replacements to their current form as advanced automation tools, PLCs have transformed the industrial landscape and continue to do so. As a PLC professional technician, I am excited to see where the future of PLCs will take us and the new possibilities that will emerge.