Hollysys assisted Qingdao Petrochemical DCS upgrade

1. Check before power-on If the cable insulation resistance meets the requirements (greater than 5M ohms), check the cable insulation resistance test record, and spot check the actual measurement if necessary. Check that all power cables, signal cables, and communication buses should be connected. Control stations, operator stations, engineer stations, etc.

1. The output accuracy is as high as 0.05%, which greatly improves the operation efficiency of the system. 2. The full-scale output of the channel signal is 0-22.7mA, and the output range is wide; 3. It can be adapted to the enhanced base to achieve channel resistance to 220VAC; 4. It has a perfect channel signal diagnosis function, which can be realized.

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. Power off 2. Cleaning the ash can not only clean the surface, but also clean the internal card key of the controller 3. If there is a supporting UPS, open the UPS and clean the ashes 4. After cleaning the ash, check whether the card and relay are loose, and tighten them if they are loose 5. The relays with frequent actions should be cleaned regularly.

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 ...

LK is a programmable controller (PLC) product launched by Hollysys for medium and high-performance control fields. It fully integrates the advantages of DCS and PLC, adopts high-performance analog processing technology, miniaturized structural design, open industry standards, and a universal system platform, so that ...

1. Switch logic control Switching logic control is the basis of PLC. It is the first use case and the most extensive of all. Replace the previous relay circuit control and realize logic sequence control; It can be used for the control of stand-alone equipment, and can also be used for group control and ...

1. Lack of motivation It may sound simple, but it's good to check the simple stuff first. Thoroughly inspect all power connections and cables for damage that could cause a short circuit. Make sure your power supply is functioning properly. Use a voltmeter to check if the grounding and voltage are correct. 2. Bad ...

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...

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.

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 ...

The "2023 China Automation + Digital Industry Annual Conference", "The 19th CAIMRS and Digital Leaders Forum" and the "Annual Award Ceremony" were successfully held in Suzhou. The theme of this summit is "Powerful Digital Intelligence, Junfa New Industry", combined with post-epidemic recovery, digital intelligence, and new industrialization.

On August 16, 2021, the Tarim Oilfield Natural Gas Ethane Recovery Project, the largest natural gas deep processing base in Xinjiang (1), a key project of PetroChina, was successfully completed and put into operation, with stable operation and the production of qualified ethane products. Tarim Oilfield Natural Gas Ethane Recovery Project ...

1. Configuration of the system and controller The configuration of systems and controllers focuses on reliability and load factor (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 ...

DCS is properly blacked out When the DCS needs to be powered off for maintenance due to overhaul or other reasons, we often directly power off the DCS, but sometimes this non-standard operation will bring serious consequences, such as configuration loss, PID parameter loss, etc. So there is a need for blackouts and re-on...

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)

In general, DCS control systems require two types of grounding: protective ground and working ground (logical, shielded, etc.). For systems equipped with safety barrier explosion protection measures, such as those used in the chemical industry, intrinsically safe premises are also required. 2.1 Protected areas (CG, Cabinet Grounding...)

1. Stand-alone control system The stand-alone control system is controlled by one PLC to control one device or one simple production line, as shown in Figure 7-1. The composition of the stand-alone control system is simple, the number of I/O points required is less, the storage capacity is small, and when the model of PLC is selected, whether there is a communication network at present.

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 ...

2. Interference in the control system and its sources On-site electromagnetic interference is one of the most common factors in PLC control system and most likely to affect the reliability of the system. It is therefore essential to know the source of on-site disturbances ...