Compare the advantages and disadvantages of PLC control with relay control and microcomputer control.

Relay control system is gradually eliminated because of its high failure rate, poor reliability, inflexible control mode and high power consumption. Although the microcomputer control system has a strong intelligent control function, it also has some defects, such as poor anti-interference, complex system design, and it is difficult for ordinary maintenance personnel to master its maintenance technology. PLC control system has attracted much attention because of its high reliability, convenient use and maintenance, strong anti-interference and short design and debugging period, and has become the most used control mode in elevator control system at present.