With the development of communication technology and control technology, as well as the popularization of industrial fieldbus. In paper-faced gypsum board manufacturers, the previous analog speed control has been gradually eliminated and replaced by more advanced fieldbus control technology. Fieldbus control relies on network technology to transmit data. Compared with the traditional analog speed control transmission speed block, it is more stable and reliable, and has higher precision.
2. Gypsum board synchronization system
Synchronous system control is an important control system in the production process of gypsum board. The control equipment is dispersed. It is composed of 1# solidification belt, 2# solidification belt, conveyor, cutting machine, acceleration after cutting 1, acceleration after cutting 2, and Dryer and other equipment composition. As shown in Figure 1. The consistent synchronization speed between the equipment can ensure continuous and stable production of qualified gypsum board, otherwise it will cause serious consequences such as longitudinal nose, bag picking, and breaking, especially in high-speed production lines. The precise synchronization speed can ensure stable production. . The system must maintain a strict synchronous speed, that is, it is required to increase/decelerate in accordance with a specific speed chain.
3. Introduction to CC-LINK bus network
CC-Link fieldbus is a PLC system-based fieldbus mainly promoted by Japan’s Mitsubishi Electric Corporation. It is currently the only fieldbus in the world fieldbus market that originated from Asia and has a certain market share. It shows strong vitality in actual engineering, especially in the manufacturing industry and is widely used. CC-LINK has the following characteristics:
(1) The fastest communication speed in the industry. When high-speed response is required, it can support large amounts of data transmission between sensor inputs and intelligent devices. The communication speed can reach 10MB within a distance of 100 meters, and the communication speed can reach 156kB at a distance of 1200 meters.
(2) The distributed PLC (Progromme Controller) is controlled and connected to the network for cyclic transmission, that is, N:N cyclic transmission is performed between the master PLC and the local PLC. The control system is fully decentralized, fully open, interoperable, and interchangeable.
(3) It can be connected to smart devices for information transmission.
In addition to the cyclic transmission of word data, the CC-LINK system can also communicate with intelligent devices, including Display devices, barcode readers, measuring devices, and personal computers.
(4) Perfect RAS function. With automatic online recovery, standby master control function, cut-off slave station function, link status confirmation function, test and diagnosis function, the system has high reliability.
(5) The multi-vendor open network has a high degree of security.
(6) Use twisted pair wires to form a bus network to save investment and improve control performance.
4. System structure overview
This system controls the master station through a Q02HCPU, executes the processing of input and output logic, calculates synchronous data, and transmits related information to each station through the CC-Link network. The CC-Link master station is located in the central control room. The PLC is responsible for collecting various information through CC-Link and displaying the operating status of the entire workshop in real time on the simulation screen. Once an abnormality occurs, it will alarm immediately to remind the operator to make a response at the first time adjust.
4.2 Remote equipment station
In the system, the encoder output of the active motor is connected in parallel to 5 inverters (FR-A540), and the CC-Link communication module (FR-A5NC) completes the speed synchronization function. At the same time, the relevant speed fine-tuning parameters can be set through the man-machine interface, and then the master station CPU communicates and sets with the inverter system through the CC-Link network module (QJ65BT11).
4.3 Monitoring equipment
The system is equipped with a man-machine interface (F-940), which is responsible for monitoring operating conditions and fault alarms. Due to the automatic loop detection function of the CC-Link network, the error information of any inverter in the network can be sent back to the master station. After the maintenance personnel obtain the relevant information in the man-machine interface, perform maintenance.
4.4 System structure diagram
The system is set to stations 1 to 7 from left to right. Each station occupies a station number, and the station type is remote equipment station. The RX and RY of each remote device station occupy 32 points, RWw and RWr each occupy 4 points. The master station is set as follows: RX M100 RYM, the communication speed is set to 625kbps according to the distance, and the system structure diagram is shown in Figure 2.
4.5 Speed chain control
There must be a certain tension in the operation of the synchronous system, so the speed of the following equipment is higher than that of the preceding equipment. The speed of the dryer operates independently but is 20% higher than the synchronous speed. When the speed of the dryer is lower than 20% of the synchronous speed, the system will alarm. The relationship of the speed chain in the measured system is shown in Figure 3.
Figure 3 Speed chain relationship
4.6 Master station network parameter setting (table 1)
4.7 Inverter parameter setting (table 2)
5.1 Inverter start
The X1 synchronization system starts, and the X2 synchronization system stops. M1 starts with a relay.
5.2 Inverter frequency setting permission
5.3 Inverter speed setting
6. Concluding remarks
This system has been widely used in many large-scale gypsum board manufacturers. Due to the CC-LINK fieldbus control method, the reliability of the system is greatly enhanced. The cost of the entire system is cheap, the wiring is very simple, and maintenance and repair are also easy. Very easy to proceed.