PLCs (Programmable Logic Controllers) have a long history, dating back to the 1960s when they were introduced as replacements for hardwired relay control systems. Over the years, they have evolved to become essential components in industrial automation, allowing for efficient and precise control of machinery and processes. Today, two of the leading PLC platforms are Siemens and Mitsubishi, each with their own unique features and capabilities. In this article, we will take a deep dive into the evolution of these PLC platforms and explore the advancements that have made them indispensable in the world of industrial automation.
Siemens, a German multinational conglomerate, was one of the earliest players in the PLC market. Their first PLC, the Simatic S5, was released in 1979 and quickly became a popular choice for industrial automation due to its flexibility and reliability. However, it was the release of the Simatic S7 series in the 1990s that truly solidified Siemens' position as a leader in the PLC industry. The S7 series introduced a modular design, allowing for easy expansion and customization, and a user-friendly programming software, Step 7, which is still widely used today.
Mitsubishi, a Japanese electronics company, entered the PLC market in the late 1970s with their MELSEC series. Their first PLC, the MELSEC FX, introduced groundbreaking features such as a battery backup for program memory and a built-in real-time clock. However, it was the release of the MELSEC Q series in 1995 that catapulted Mitsubishi to the forefront of the PLC industry. The Q series offered improved performance, a larger memory capacity, and a range of specialized modules for various industrial applications.
Both Siemens and Mitsubishi have continued to innovate and improve their PLC platforms over the years, introducing new series and models with advanced features and capabilities. One significant development in the world of PLCs was the integration of communication protocols, such as Profibus and Ethernet, allowing for seamless connectivity and data exchange between PLCs and other devices. Both Siemens and Mitsubishi have incorporated these protocols into their PLC platforms, making them more versatile and interoperable.
Another crucial aspect of PLCs is their ability to handle and process large amounts of data. As technology has advanced, the need for faster and more efficient data processing has become increasingly important. Siemens has addressed this with the release of their Simatic S7-1500 series, which boasts a powerful processor and a high-speed backplane bus, allowing for faster execution of complex programs. Mitsubishi, on the other hand, has introduced the MELSEC iQ-R series, which utilizes a multi-core processor and a high-speed module bus for improved performance and data processing capabilities.
In recent years, the concept of Industry 4.0 has gained traction, promoting the integration of digital technologies in manufacturing processes. As a result, PLCs have evolved to become smarter and more connected, with features such as remote access and cloud connectivity. Siemens has embraced this trend with their TIA (Totally Integrated Automation) portal, which allows for the seamless integration of all automation components, including PLCs, into a single platform. Mitsubishi has also introduced their iQ-Platform, which offers similar capabilities, including cloud-based data monitoring and management.
One area where Siemens and Mitsubishi differ significantly is their programming languages. Siemens primarily uses the IEC 61131-3 standard, which includes programming languages such as ladder logic, structured text, and function block diagram. This standard is widely accepted and allows for a more standardized approach to programming PLCs. On the other hand, Mitsubishi uses their own proprietary language, GX Works, which is based on ladder logic but has some unique features and functions that are not found in other programming languages.
In conclusion, the evolution of PLCs has seen them become an indispensable part of modern industrial automation. Siemens and Mitsubishi, two of the leading players in the market, have continuously improved and innovated their PLC platforms to meet the ever-changing demands of the industry. With features such as modularity, advanced data processing, and connectivity, these platforms have become essential tools for efficient and precise control of industrial processes. As technology continues to advance, we can expect to see even more advancements and developments in PLCs, making them even more integral to the world of industrial automation.