Hollysys PLC - the characteristics of the working process of PLC

Kunming Changshui International Airport is one of the eight regional hub airports in China and one of the five national large-scale gateway hub airports. With the rapid economic development of Yunnan Province, the aviation business volume of Kunming Airport has grown rapidly.

1. Correctness (low debugging cost) First of all, the PLC program must be able to work correctly to meet the requirements of the actual control process. This is the essence of the PLC program, and if you don't do that, nothing else makes sense. 2. Reliability (low maintenance cost) Not only to ...

Recently, Hollysys signed a contract for the comprehensive management platform project of smart tunnel of Linzhou-Changzhi Expressway in Henan Province. Linzhou to Changzhi Expressway is a traffic artery that crosses the Grand Canyon of Taihang Mountain, through Henan and Shanxi, with a total of 7 pairs (14) tunnels.

Simplicity Make the PLC program as simple as possible. Simplicity means using a standardized procedural framework as much as possible and using simple instructions as much as possible. If you want the program to be simple, in a big way, you should optimize the program structure, simplify the program with process control instructions, and ...

1. Open empty A master air switch that is the power control for the entire cabinet. 2. Power supply A 24VDC switching power supply. 3、PLC This should be chosen according to the needs of the project. If the scale of the project is small, the integrated PLC can be used directly; If the item ...

1. The role is different A PLC (Programmable Logic Controller) is an electronic system designed for digital operations in an industrial environment. The inverter is the application of frequency conversion technology and microelectronics technology to control the AC motor by changing the frequency of the motor working power supply.

1. What is a communication protocol? A communication protocol is an agreement between two parties to a communication. The agreement includes uniform provisions on data format, synchronization mode, transmission speed, transmission steps, error detection and correction mode, and control character definition, etc., which must be complied with by both parties to the communication. Therefore...

(1) When the PLC and the host computer (or touch screen) form a monitoring system, there are many times when there are "manual", "automatic" and other control modes on the screen (generally when there is only one multiple). You can use the "MOV" command in the program. For example, when "manual" is selected, the constant 1 MO ...

1. High reliability Because DCS disperses the system control function on each computer, and the system structure adopts a fault-tolerant design, the failure of one computer will not lead to the loss of other functions of the system. In addition, due to the fact that the tasks undertaken by the various computers in the system are comparatively ...

Facing China's "double carbon" strategic goals, the Beijing Economic and Technological Development Zone is guiding a large number of enterprises to explore the implementation plan of "carbon peak" and "carbon neutrality", and strive to build a number of green factories, green products and green supply chains. Recently, enterprises in the zone and Lisi Group signed a contract for the first time in China to use CO (dioxide...

(1) Development in the direction of integration: the development of standardized data communication links and communication networks, and the formation of a large system of various single (multi) loop regulators, PLCs, industrial PCs, NCs and other industrial control equipment to meet the requirements of factory automation and adapt to the general trend of openness. (2) To the intelligent ...

1. Communication network failure: communication network faults are generally easy to occur at the contact bus and local bus, or caused by wrong address identification. 2. Node bus failure: The transmission medium of the node bus is generally coaxial cable, some use token signal transmission mode, and some use ...

1. The switching quantity is also called the logical quantity, which means that there are only two values, 0 or 1, ON or OFF. It is the most commonly used control, and controlling it is the advantage of PLC, and it is also the most basic application of PLC. The purpose of switching control is to follow the current input combination with the historical input according to the switching quantity.

Whether it is a new unit or an upgraded DCS, the equipment of the system and controller should focus on the reliability and load factor (including redundancy) objectives. The load rate planning of the communication bus must be controlled within a reasonable range, and the load rate of the controller should be balanced as much as possible.

From November 15th to 17th, the 2022 China Nuclear Energy High-Quality Development Conference and Shenzhen International Nuclear Energy Industry Innovation Expo (hereinafter referred to as the "2022 Shenzhen Nuclear Expo") will be grandly reopened at the Shenzhen World Convention and Exhibition Center. 　　The theme of this year's Nuclear Expo is "Nuclear Gathering in the Bay Area, Activating the World".

1. The application form of PLC in CNC machine tools PLC is used in CNC machine tools, and there are usually two forms: one is called built-in: the other is called free-standing. Built-in PLC is also known as integrated PLC, the CNC system in this way, at the beginning of the design of the NC and PLC combined ...

Examining the hierarchical structure of DCS, DCS level and control management level are the two most basic links that make up DCS. The process control stage specifically realizes the decentralized control functions such as signal input, conversion, operation and output. The controls at the process control level vary in different DCS, ...

Various brands of PLCs have a self-diagnosis function, but the trick of PLC repair is to make full use of this function to analyze and then pinpoint the problem. Sorted out the 8 common types of errors that PLC repairmen need to know when the PLC presents abnormal alarms. 1. CPU abnormality ...

1. Open empty A master air switch that is the power control for the entire cabinet. 2. Power supply A 24VDC switching power supply. 3、PLC This should be chosen according to the needs of the project. If the scale of the project is small, the integrated PLC can be used directly; If the item ...

Analog signal: refers to a continuous current signal or voltage signal, and analog signal can be divided into standard signal and non-standard signal. Switching signal: It can be divided into active signal and passive signal, which is basically an on-off signal, and can be measured on and off with a multimeter ohm. ...