the method used by the plc to write a ladder logic program is called

Then someone got the idea to program the PLCs with the ladder diagram, which allowed the industry to repurpose existing skill sets for programming. When PLCs arrived, they promised a lot of benefits to automation, but nobody knew how to program them. The circuit would be documented in a standard structure that resembled a ladder when drawn on paper, hence the name “ladder diagram” (see Figure 1). There wasn’t a programming role there was an engineer to design the circuit and an electrician to assemble it. Ladder logic originsĪutomation existed before PLCs, frequently using a network of relays for the brain of an application.

The question is, though: How well can ladder logic serve the complex automation needs of the present and future compared to other programming languages? The answer is more complicated than just contacts and coils. Ladder logic, the primary programmable logic controller (PLC) programming language, is simple and represented graphically as relay contacts and coils. Ladder logic is favored by manufacturers in discrete industries, but as technology and automation evolve, its usefulness compared to other IEC 61131-3 programming languages and PC programming depends on application complexity and other factors. Nine considerations when selecting a programming language.

The method used by the plc to write a ladder logic program is called