PLC stands for Programmable Logic Controller, a digital electronic system designed for industrial applications. It uses a programmable memory to store programs, execute user-oriented instructions for logical operations, sequential control, timing, counting, and arithmetic operations, and control various types of machinery or production processes through digital or analog inputs/outputs.
PLC communication methods mainly include RS232, RS485, PPI/MPI, PROFIBUS DP/PA/FMS fieldbus, Ethernet bus, DEVICEnet bus, and wireless network. With the limitations of local communication control, remote control network communication, using wired and wireless methods, is gradually becoming mainstream. Ethernet communication and wireless network communication are gradually replacing the original local serial port or bus control methods in PLC remote control.
The system utilizes the Xinyangbang DTU, a 433M wireless autonomous network device, via an RS485 bus and the Modbus RTU protocol to achieve point-to-multipoint PLC master-slave relationships. Local wireless remote monitoring is achieved through a serial port connection with the touchscreen software. Furthermore, wireless remote human-machine interface management and monitoring are implemented via a bus connection to the Xinyangbang DTU product through a GPRS/CDMA network and a virtual serial port (IO/device) in KingSCADA software.
A 433m wireless self-organizing network was used to implement RS485 bus cabling. Point-to-point (point-to-multipoint) wireless communication was achieved through a wireless DTU. This eliminated manual cabling costs and simplified the project schedule.
The system utilizes a wireless self-organizing network to centrally manage and monitor data via a touchscreen configuration. It features cascading wireless communication modules, enabling remote management and control via remote network management software. This eliminates the need for manual inquiries and allows for unattended operation. The system also improves the centralized remote management interface, facilitating remote control and reducing subsequent operation and maintenance costs.
The Xinyangbang DTU SMS modem S-DT411 is a wireless data acquisition and transmission control terminal. It can realize remote human-machine interface control with KingSCADA software, and also has SMS receiving center and SMS control functions. It can query PLC real-time analog and digital information at any time, and can remotely modify PLC configuration and parameters via SMS commands.
Employing 2G/3G/4G network standards ensures network coverage and widespread adoption, supporting operator APN/VPN, and using encrypted communication methods to effectively guarantee the security of APN private network data communication. It can also be overlaid with Xin Yang Bang DTU's built-in DES, AES, and 3DES proprietary encryption methods to achieve single-layer/dual-layer wireless encryption, ensuring secure and reliable data communication. This guarantees the security and effectiveness of modern industrial automation control.
