PLC programming skills, special function modules and touch screen

Programmable Controller (PC or PLC for short) is an electronic system for digital computing operations, specially designed for use in industrial environments.

The programmable controller was developed based on electrical control technology and computer technology, and has gradually developed into a new type of industrial control device with a microprocessor as the core, integrating automation technology, computer technology, and communication technology.

At present, PLC has been widely used in the automatic control of various production machinery and production processes, becoming one of the most important, most popular and most widely used industrial control devices. It is recognized as one of the three pillars of modern industrial automation (PLC, robots, CAD/CAM).

It is easy to get started with programmable controllers, but if you want to truly master the programming methods of programmable controllers, you must be able to smoothly design programs that meet the requirements of production tasks, and at the same time make the programs concise and easy to understand. For beginners engaged in PLC applications, systematic learning of PLCs is very important.

Below, the editor will share with you the PLC programming skills, special function modules and touch screen learning methods, hoping to be helpful to everyone.

Collect more program examples and increase programming experience

In the PLC programming method, collecting data is very important.

1. Collect typical program samples. It is best if the program has relatively complete components: control tasks, I/O allocation, hardware wiring diagram, complete program and comments.

2. You need to understand the program and break it down into its components that are used to complete different tasks. The subroutines or interrupt programs that independently complete a specific function in each component should be promptly collected into the program library.

This will save programming time and improve the success rate of program debugging when you encounter similar control tasks in future programming processes.

3. Record the highlights of the program, such as the programmer’s clever ideas, program structure, and the use of application instructions.

In particular, the use of application instructions can greatly shorten program length, reduce memory capacity and lower system costs.

4. Design and debug the program's functional extensibility, and record and summarize the entire process in detail.

Through the above process, you can effectively digest these program examples and integrate them into your future programming process.

2. Proficient in using software packages

Take the study of Mitsubishi products as an example to introduce the use of software packages.

Mitsubishi software package consists of two parts, programming software GXDeveloperVersion8C and simulation software

GXSimulator6C.

The programming software GX Developer Version 8C provides a programming environment for designers.

Designers should be familiar with programming manuals and master program editing techniques so that their own design plans can be presented.

Whether the designed program can meet the control task, it must be debugged. The traditional debugging method is inseparable from the programming controller CPU. If necessary, it is also necessary to prepare input and output modules, special function modules and external machines.

The simulation software GXSimulator can provide a virtual experimental platform.

GXSimulator is a software package that runs on Windows. By installing GXSimulator on a computer with GXDeveloper installed, offline debugging can be achieved.

The offline debugging function includes monitoring test of soft components, simulation operation of I/O of external devices, etc.

For personal learning, without experimental conditions, simulation software can be used to develop and debug sequential control programs on personal computers.

Through continuous simulation and debugging of the program, users can gradually understand the programming experience and thus increase their programming experience.

Three special function modules

During the learning process, most students focus on software programming. However, modern industrial control has brought many new challenges to PLC. If general I/O modules are used to solve these problems, the hardware cost is too high and the software programming is quite troublesome. Some control tasks cannot even be completed with general I/O modules.

Therefore, it is particularly important to learn the special function modules of PLC.

These special function modules include analog input and output modules, high-speed counting modules and motion control modules.

The PLC manufacturers of these special function modules have provided detailed user manuals. Users can complete the implementation of special functions by carefully reading the user manuals, which simplifies software programming and reduces economic costs.

Four-person machine interface

A digital device that connects to a programmable controller, uses a display screen to display, writes working parameters or inputs operating commands through an input unit (such as a touch screen, keyboard, mouse, etc.), and realizes information interaction between humans and machines is called a human-machine interface, commonly known as a touch screen.

With its advantages of ease of use, durability, fast response speed and space saving, the touch screen makes system designers increasingly feel that the use of touch screens does have considerable advantages.

The touch screen consists of two parts: hardware and software.

The software can be used to design the user interface, and combined with the PLC program design, it greatly simplifies the use of computers. Even people who know nothing about computers and operators who do not understand PLC programming can set control system parameters, production recipe storage, equipment production data recording and other operations according to control requirements.

The learning of touch screen can be carried out in the following steps:

First, carefully read the screen design manual for a series of touch screens to design the user screen;

Then design the touch screen screen operation to implement the corresponding PLC program;

Finally, open the touch screen and PLC programming simulation software for simulation debugging.

5. Master the mainstream products of three genres

It can be roughly divided into three main schools according to region:

1. Japanese products, represented by Mitsubishi FX series small PLC;

2. American products, represented by AB company's PLC series medium-sized PLC;

3. European products, represented by Germany's Siemens S7 series large PLC.

Different types of PLC products have different characteristics, which are not only reflected in special and complex functions, but also in programming languages, program organization and other aspects.

It is obviously unrealistic and unnecessary to master all PLC products.

On the basis of mastering one PLC product, consciously select the most representative products from other major schools and use comparative learning methods to conduct relatively in-depth research.

In this way, when you encounter other models in future work, study, development and research, you will be able to apply what you have learned to other similar cases.

6. Make full use of network resources to grasp the latest information on PLC application and development

PLC products are updated and replaced very quickly. If you want to keep abreast of the latest information on PLC applications and developments, you must make full use of the learning platform provided by the Internet to grasp the latest PLC developments conveniently, quickly and economically.

For example, the Compass Robot training can provide us with a large amount of learning materials, user manuals, etc., which greatly benefits learners at different stages.