and Lisi DCS - the difference between DCS control and PLC control

1. PLCZ self-fault judgment In general, PLCs are extremely reliable devices with a very low failure rate. The probability of hardware damage such as the CPU of the PLC or software running errors is almost zero; If the PLC input point is not caused by strong current intrusion, it will hardly be damaged; PLC output relay ...

Recently, the signing ceremony of the strategic cooperation between Bureau Veritas and Hollysys and the functional safety certification ceremony of Hollysys valves were held in the Hangzhou base of Hollysys. Mr. Ye Jiong, General Manager of Bureau Veritas Technology Center, Mr. Zhong Aimin, Director of Product Certification Center, Mr. Yang Yang, Sales Director of Eastern Region, and Mr. Yang Yang, Director of Functional Safety ...

3. Main anti-interference measures (1) Reasonable treatment of power supply to suppress the interference introduced by the power grid For grid disturbances introduced by the power supply, an isolation transformer with a shielded ratio of 1:1 can be installed to reduce the interference between the equipment and the ground.

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...

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...

1. The connection line is loose and the contact is poor When the run indicator of the PLC turns red, the position of the plug changes to green with a manual move, indicating that the plug is loose, and it is best to replace the new connecting wire, and the plug is frequently plugged and unplugged, which will also lead to poor contact. 2. Strong electrical interference (external)

On October 18, 2022, the China Intelligent Transportation Association released the list of winners of the "2022 China Intelligent Transportation Association Science and Technology Award", which includes the Science and Technology Progress Award, the Technology Invention Award, and the Outstanding Innovative Talent Award. Among them, Beijing Hollysys System Engineering Co., Ltd. ...

On September 19, 2022, the XCon2022 Security Focus Information Security Technology Summit was successfully held in Beijing. More than 10 technical experts, heads of security departments, and front-line security experts from well-known domestic network security enterprises shared in-depth topics at the meeting.

1. Field instrument equipment failure: Field instrumentation equipment includes various transmitters, various switches, actuators, loads and components of various temperatures that are directly connected with the production process. If the field instrument fails, it directly affects the control function of the DCS system and the operator's ...

Serial communication is done using 3 wires: (1) ground, (2) sending, and (3) receiving. Since serial communication is asynchronous, ports are capable of sending data on one wire and receiving data on the other. Other threads are used for handshakes, but are not required. Serial communication is the heaviest ...

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...

1. The configuration of the system and controller should focus on reliability and load rate (including redundancy). The communication load rate must be controlled within a reasonable range, and the load rate of the controller must be balanced as much as possible to avoid the occurrence of "high load" problems. 2. The distribution of system control logic should not be too much.

01 Node bus failure The node bus material is usually a coaxial cable, so as long as there is a cable disconnected, the communication of all devices on the bus will be paralyzed, which will cause serious phenomena such as data loss, equipment stoppage and operation interruption, and may eventually directly or indirectly cause huge ...

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 ...

On November 13, 2022, Zhong'an United Coal Chemical Branch came with exciting news that the 20,000 tons/year butene-1 plant produced qualified butene-1 products at 22 o'clock on the same day, and the one-time start-up was successful. The control system of the device adopts the innovative technology product "OCS Industrial Optical Bus Control ...

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 ...

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...

Recently, Hangzhou Hollysys Automation Co., Ltd. (hereinafter referred to as Hollysys Company) successfully signed a contract with PetroChina Liaoyang Petrochemical Branch (hereinafter referred to as PetroChina Liaoyang Petrochemical) to construct and rectify 16 sets of control system projects during the planned overhaul in 2023 - 9 ...

1. Use the analog output module of the PLC to control the analog output module of the inverter The analog output module of the PLC outputs a 0-5V voltage signal or a 4-20mA current signal, which is used as the analog input signal of the inverter to control the output frequency of the inverter. This control method is simple to wiring, but it needs to be selected and changed.

1. The function of PLC PLC is a general industrial automatic control device with microprocessor as the core, integrating computer technology, automatic control technology and communication technology, which has high reliability, small size, strong function, simple program design, flexible and universal and maintenance methods.