PLC control system Based on the cha

PLC control system Based on the characteristics of PLC, PLC: flexible use and powerful versatility-standardization of PLC hardware, further serialization of PLC products, the flexibility to form control system with different sizes and different functions There are many functional module types. In a control system consisting of a PLC, only the corresponding input / output signal line needs to be connected to the PLC terminal. If you need to change the functionality of your control system, you can use the programmer to change your program online or offline. The same PLC device is used for different control objects, but with different input and output components and application software. High reliability and strong anti-interference ability-a powerful microcomputer, but with common anti-interference ability, electromagnetic interference, power fluctuations, mechanical vibration, weak temperature and humidity changes at industrial sites, common general. The microcomputer may not work properly. Traditional relay-contactor control systems have strong anti-interference capabilities, but the large number of mechanical contacts (easy to wear and ablate) result in short life and unreliable systems. PLCs use microelectronics technology and contactless electronic storage devices complete a number of switching actions. Most relays and complex wiring have been replaced by software programs, which prolong life and greatly improve reliability. The average trouble-free time for PLC control systems is usually up to 40,000-50,000 hours. PLC adopts a series of hardware and software anti-interference measures. It is adaptable to various industrial fields with strong interference and has self-diagnosis function of failure. For example, a typical PLC can withstand the interference of 1000V and 1ms pulse, and its working environment temperature is 0 ~ 60 ℃ without forced air cooling.