What are the characteristics of PLC and relay contactor control in working mode?

PLC is mainly controlled by program, and relay is controlled by machinery. Generally, small and simple lines with single logic can be controlled by machinery, saving costs. Large and medium-sized lines, as well as projects with complex logic, are all controlled by PLC, which can output different control methods according to different program logic. PLC control has strong expansibility, and relay control is troublesome to expand.

At present, the general control circuit is PLC control, relay isolation operation, stroke interlocking in program and machinery, which ensures the control effect and terminal equipment well.