The Difference between PLC and Industrial Computer
About PLC
The full name of PLC in English is Program mable Logic Controller, which was produced in the early 1970s. The earliest PLC appeared in the role of replacing the relay system, and its main function was only a simple logic sequence control function.
After decades of development, PLC is specially designed for sequential control using computer principles, and it is also versatile and easy to use. PLC adopts proprietary hardware design, which can provide safe and reliable control applications and relatively complete solutions for a variety of automation equipment. Generally speaking, the function of PLC is relatively single, with strong stability and low cost.
About Industrial Computer
Industrial Computer adopts PCI bus and PC/104 bus based on the characteristics of the computer. In terms of processing performance, the industrial computer can have a powerful CPU, integrate a wealth of I/O interfaces, and have advantages in computing, storage, networking and software openness, and also have function expansion boards to connect to I/O points to realize PLC control. Function. In general, the performance, operation and maintenance computing capability of the industrial computer is stronger than that of the PLC.
There are obvious differences between PLC and industrial computer in terms of technical characteristics, but they are constantly absorbing each other's advantages to adapt to different application sites.
The differences between industrial computer and PLC
1. Hardware structure. Both industrial computer and PLC are composed of central processing unit CPU, memory, input and output devices, etc. PLC is a special calculator, but it has a different bus architecture from industrial computer.
2. Cost-effective. Both industrial computer and PLC have the characteristics of high performance, high integration, modularization, mass production and wide application. When there is no more complex data processing, graphic display or motion trajectory requirements in the designed control system, PLC can be used to obtain better cost performance. Therefore, the general ordinary pipe bending machine can meet the requirements by using an integrated PLC. Its control cost is also relatively low, otherwise, only the control system composed of industrial computer + board or industrial computer + PLC can be used.
3. Peripheral configuration. Compared with PLC, IPC has more abundant peripheral devices, such as monitors, drivers, printers, network interface cards, etc., and they are all standard components. The PLC has fewer types of peripherals and is more specialized, and peripherals of different brands cannot be used universally.
4. Human-machine interface tools. A touch industrial display is a tool that connects humans and PLCs. It can be used for parameter setting, data display, depicting the automatic control process in the form of curves and animations, and can simplify the PLC program. Compared with traditional analog instruments and button consoles, it is smaller in size and simplifies control wiring.
5. Programming tools. For industrial computers, high-level languages such as C language can be used for programming, so that the written application program is easy to modularize and has strong operational logic, but the software preparation time is long, debugging assistance, and software programmers need to have higher software and hardware knowledge, while PLC The ladder diagram is used, the software and hardware development cycle is short, and the maintenance and fault diagnosis are easy.
