For most systems, there are various languages meant for specific purposes, including Function Block, Sequential Charts, and Structured Text. By far, the most common programming language for PLCs consists of rungs of if-then logic, similar to an electrical line diagram, going by the name of ‘Ladder Logic.’ Many programmers have quite likely been exposed only … Read more
Many PLC commands are well-known to programmers, including contacts, coils, timers, and counters. But a less-common instruction is the one-shot, capable of harnessing the incredible processing speeds in a CPU. One-Shot Functions In a previous article, I wrote about how to use timers in ladder logic. A typical next step is to discuss counters, being … Read more
In this first of an upcoming series, we investigate Siemens as a major PLC manufacturer, learning about the hardware, software, and key applications of each product lineup. Siemens AG is the largest energy and industrial manufacturing company in Europe, and with more than 170 years of history, it is also an innovator in many fields. … Read more
An overview of the requirements, standards, applications, and main differences between Profinet and Profibus communication protocol, connectors, and evolution from its original technology. Profibus and Profinet are two of the most popular communication protocols used in industrial automation. Both protocols share a similar origin story, as they were conceived out of the need for standardizing … Read more
What software languages are used with programmable logic controllers? What software languages are used with programmable logic controllers? An important part of using programmable logic controllers (PLCs) IEC 61131-3 is part three of the international standard for programmable logic controllers. In this section of the standard, the software architecture and valid programming languages of a … Read more
This article will introduce Modbus, an industrial protocol that laid the foundation for fieldbus communication in industrial systems. In 1979, Modicon introduced an application layer protocol (layer 7 of the OSI model) for use with its Programmable Logic Controllers (PLC). This protocol was called Modbus and became the first widely used fieldbus in the history … Read more
Mitsubishi’s FX series PLC is one of MELSOFT GX Developer’s most popular automation solutions for small and medium-scale applications. Learn how to use GX Developer software to program the FX series PLC. The FX series PLC is one of the introductory MELSEC product lines from Mitsubishi Electric. The company is widely recognized for the manufacturing … Read more
This article describes the programming language ladder logic used to program PLCs and shows examples of how it functions. Ladder diagram, better known as ladder logic, is a programming language used to program PLCs (programmable logic controllers). This article will briefly describe what ladder logic is and go over some examples of how it functions. … Read more