Industrial control computer and programmable controller itself has a high degree of reliability, but if an error occurs the switch signal input to the PLC, analog signals deviate, PLC outputs control of actuators are not required, these may make the process go wrong, causing irreparable economic loss.Affect the signal input to the PLC error the … Continue reading Input to the PLC the main cause of an error signal and actuator

When PLC inputs the input signal changes PLC output reacts to the input changes will take some time, a phenomenon called the PLC input/output response lag.From the above analysis, scanning cycle length depends on the length of the program. Scan cycle is longer, respond more slowly. As each scan cycle is only one I/O refresh, … Continue reading PLC input/output response lag and its effect analysis

PLC input modules are used to detect incoming field input signal and converts the input signal within the PLC accepts low-voltage signal. 1. Input signal type and voltage selection switch input signal types there are three types of modules: DC input and AC and AC/DC input. General according to the input signal and the surrounding environment … Continue reading How to choose PLC switch input module?

Output modules are PLC internal low voltage signal can be converted to an external output device required to drive signals. Main load voltage should be considered when choosing the type and size, system requirements, to delay load state changes are frequent, and so on. 1. Choice of outputDigital output modules have three output: relay output, transistor … Continue reading PLC digital output module selection

PLC programming languages and computer languages, have distinctive features, which is different from a high-level language, and with the General Assembly, it is both easier to write, and to meet the requirement to debug. At present, there is no programming language to the manufacturers of products are compatible. If Mitsubishi products has its own programming … Continue reading Basic instruction of PLC system features

When the PLC system is designed, first determine the control scheme, the next step is the design of PLC type selection. Characteristics of process design and application requirements are the main basis for selection. PLC and related equipment should be integrated, standard, as easy to form a whole and industrial control system, easy to extend … Continue reading PLC industrial control selection methods

This section of the PLC of the structure and characteristics of the hot issues of the solution, so that beginners PLC has an overall knowledge.Q: what is a PLC (programmable logic controller)?Answer: PLC can series program device (Programmable Logical Controller) is a digital operation operation of electronic system, designed for industrial environment Xia application and … Continue reading PLC overall composition and characteristics

PLC (programmable logical controller, PLC for short) has been increasingly used in industrial control systems, and plays a very important role in the automatic control system. Therefore, it is very important for the correct selection of PLC.Numerous suppliers of various types of PLC, each of them has advantages and disadvantages, to meet user needs, but … Continue reading Correct selection of PLC in the automatic control system design

The structural variety of programmable controllers, but the General principles of its composition are basically the same, are based on the microprocessor architecture. Usually consists of a central processing unit (CPU), memory (RAM and the ROM), input/output (I/O), power supply and programmer in several parts.1. The central processing unit (CPU)CPU as the core of PLC, … Continue reading PLC’s structure and function of each part

PLC late 60 in the United States, comes first, and was called the programmable logic controller PLC (Programmable Logic Controller), aims to replace the relay, to perform a logical sequence control functions such as judgment, timer and counter. PLC's basic design idea is to computer functions, flexible, general advantages and relay control system easy to … Continue reading PLC (Programmable Logic Controller) introduced