Hollysys DCS - the selection, design and debugging of DCS system

PLC understands the interrupt function in this way, when understanding the interrupt, we must first understand the PLC operation cycle or the scanning cycle, it is necessary to say that the PLC sequential control cycle execution process, which is the premise of understanding the interrupt, must be mastered, divided into three parts, input processing, program processing, output ...

1. View the data on the monitoring screen When the following situations occur, it means that there is a problem with the control system, and the microcomputer maintenance personnel should be notified immediately for maintenance, and the operator should go to the site to deal with it. (1) Frequently changing data does not change for a long time, and several or all data do not ...

1. PLC programmable logic controller (programmable controller). 2. DCS system pays more attention to the field of process control. Such as chemical, smelting, pharmaceutical, etc. It mainly monitors and controls some field parameters, while PLC focuses on logic control. machining). Of course, the PLC's ...

Hollysys Automation provides automation solutions for many fields. 　　Intelligent TCM solutions In order to make the drug achieve the harmony and unity of the doctor's peace of mind, the pharmacist's formula, and the patient's peace of mind, higher requirements are put forward for the pharmacy environment and hospital management. But...

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.

According to the structural form of PLC, PLC can be divided into two categories: integral type and modular type. (1) Integral PLC The integral PLC is a centralized power, CPU, I/O interface and other components in a chassis, which has the characteristics of compact structure, small size and low price. Small PLC ...

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.

Merit: 1. High reliability: The DCS system has multiple redundancy, backup and recovery mechanisms, which can ensure the high reliability and stability of the system. 2. Sensitivity: The DCS system can be customized according to different industrial processes to meet different control requirements. 3. Efficiency: D...

1. Scanning technology When the PLC is put into operation, its working process is generally divided into three stages, namely input sampling, user program execution and output refresh. The completion of these three phases is called a scan cycle. During the entire operation, the CPU of the PLC scans at a certain speed ...

1. Logic control of switching quantity This is the most basic and most extensive application field of PLC, which replaces the traditional relay circuit to achieve logic control and sequence control, which can be used for the control of a single device, as well as for multi-machine group control and automatic assembly line. Such as injection molding machines, printing machines, ...

With the inclusion of "exploring the construction of digital twin cities" in the 14th Five-Year Plan, the field of intelligent transportation is being endowed with more new business value. Recently, Century Qualcomm and Hollysys reached a strategic cooperation, based on the principle of "giving full play to advantages, mutual promotion, long-term cooperation, mutual benefit and win-win", ...

Hangzhou Hollysys Automation Co., Ltd. (hereinafter referred to as Hanghe) and Jinan Iron and Steel Group International Engineering Technology Co., Ltd. (hereinafter referred to as Jinan Iron and Steel International) signed a strategic cooperation agreement in Jinan. Luan Yuandi, Deputy General Manager of Jinan Iron and Steel International, Sun Jiaying, Director of the Automation Division, and Liu Xinjie, Director of the Automation Office...

The control system needs to establish the input and output channels of the signals, which is called I/O. The I/O in a DCS is generally modular, with one or more I/O channels on one I/O module for connecting sensors and actuators (control valves). The control unit of the DCS: a process control station is ...

First, the type of failure of the PLC. 1. External equipment failure. External equipment refers to various switches, sensors, actuators, loads, etc., which are directly connected with the PLC operation process. The failure of these equipment will directly affect the control function of the PLC system. Therefore...

1. Data backup When carrying out maintenance, we must cut off the power, data backup between power outages is an important link, for the data that needs to be archived for a long time, you can back up the historical trend data to the mobile hard disk, and then turn off the Windows-based operating system (Note...

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.

01. Power supply The DCS power supply system is mostly a "dual backup hot redundant power supply", and the prevention and control of power failures is mainly reflected in the inspection and daily maintenance. Generally speaking, as long as the unit is normal ...

According to the different functions of PLC, PLC can be divided into three categories: low-grade, mid-range and high-end. (1) Low-grade PLC Low-grade PLC has basic functions such as logic operation, timing, counting, shifting, self-diagnosis, monitoring, etc., and can also have a small amount of analog input/output, arithmetic operation, math...

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 ...

Recently, identified by the Beijing Software and Information Service Industry Association, after a strict audit and evaluation process, in accordance with the relevant provisions of the national "Software Enterprise Evaluation Standards" and "Software Product Evaluation Standards", the China Software Industry Association announced the latest batch of "software enterprises" list, Beijing Heli ...