1. Overview
based Biodegradable plates of the double-sided waterproof adhesive glue production process requirements and program design and development for our customers and created the Biodegradable plate automatic two-sided waterproof plastic coating line. The automatic coating line from the blanking plate, 3 spray, 6 baking, turning it over and transfer robot, cutting, automatic sorting packaging, conveyor chains etc., all require automatic control, and debugging convenience, all across the board relatively independent of process equipment, I / O points more (about 520 I / O points) and the distribution is more scattered.
of the above, such as centralized control by PLC, cable laying capacity, for which we based on the use of distributed control method to achieve distributed control, such as the use of large-scale PLC bus communication module with remote I / O module, high cost, by contrast, Schneider Twido series PLC has built-in communication module, communication strong, able to meet the control requirements, and the higher cost, and Schneider Electric can provide from the HMI and PLC, PLC and inverter Modbus serial device communication between the seamless integration of low-cost complete solution.
2. the system hardware configuration
the coating line electrical control system has two components: the upper layer of the integrated monitoring, the main component of industrial touch screen, through MODBUS bus to communicate with the PLC to complete the full range of graphic display device status and parameters set set; lower for the control layer, from 6 sets of Twido PLC composed of six sets of relative upper touch screen PLC are from station 6 sets the scene PLC automatic feeding of the respective plate, three sets of automatic spray system, spraying, drying and curing equipment, temperature, tray flip transfer robot, automatic off the assembly line, packaging and conveyor sorting control, which 1 # PLC Modbus bus and drive through two conveyor communicate inverter control, 6 # PLC via Modbus bus communication with local industrial touch screen, complete the local device s operation, parameter setting and monitoring. System architecture shown in Figure 1.
Figure 1 plate automatic painting line diagram of electrical control system structure
1) Industrial Touch Screen
This machine adopts Schneider with Ethernet communication port and the monochrome STN s XBTG series of touch-screen each one as a graphic display unit, one of the built-in Ethernet, for future system updates to stay Under the interface, synchronous link Uni-Telway, Modbus and ModbusTCP / IP and other communications. XBTG terminal to use VijeoDesigner VJDSPUL software Windows environment configuration and page design, through the use Java language script, in XBT G terminal can handle all kinds of information.
touch screen as the full range of control equipment is used to: coordinate 6 sets from the station PLC controlled equipment coordination and data communication equipment which will form an organic line of interconnected control systems; monitoring display across the board the state of equipment; provide all equipment, statistical and maintenance actions and alarmed; password set by the operation of rights and other agencies.
2) PLC configure each PLC by DC power, CPU module, I / O and communications modules. The PLC main configuration the following table:
them in order to prevent power fluctuations impact on the PLC is running, the use of isolation transformers and DC24V power supply as the PLC power supply and control power.
as Twido expansion I / O drive a smaller (16 points or more transistors DO module drive capacity is only 0.1A), we use MosFET control solid state relay board (see Figure 2) PLC amplification and then drive the output load.
6 platform data exchange between the PLC and associated control through the touch screen with the upper XBTG Java language script to complete. Across the board has several emergency stop buttons and safety relay protection circuits, to ensure the safety of personnel and equipment operation.
3) transmission frequency converter configured using Schneider Inverter ATV58, for a given conveyor speed, ATV58 Inverter Built-in Modbus communication interface, 1 # PLC using Modibus bus communication on the two inverter to complete the two transport Machine speed synchronization, operational control, status monitoring. Two conveyor is fully synchronized, is a continuous operation of the automatic coating lineLine key, as machinery manufacturing and the error, Bixujinxing speed synchronization control, two Shusong machine speed and position via encoder feedback to 1 # PLC, You Hou PLC by PID operation carried out against both conveyor speed of fine-tuning to reach an fully synchronized.
3. Conclusion <BR> the radio control system has the following advantages:
(1) Modbus serial communication through the completion of complex large-scale automatic coating line control, reduce costs
(2) full range of stable operation, high efficiency, high degree of automation, with complete protection and alarm functions and so on.
(3) man-machine interface XBTG and Twido PLC support Modbus TCP / IP and CANopen and other communications left for future system updates interfaces.
(4) improved fault detection and alarm function, ensure that equipment is reliable.