The invention relates to the industrial
automation control technology field and relates to a mixed redundancy programmable
control system based on equipment redundancy and
network redundancy. The mixed redundancy programmable
control system comprises a main controller mixed redundancy
system and a secondary controller mixed redundancy
system, and four levels of redundancy, such as double-
Ethernet-equipment redundancy,
Ethernet equipment redundancy, double-serial-port serial
network redundancy and serial equipment redundancy are included. A main controller is a controller of a double-
Ethernet port, four-line mechanism realizes mixed redundancy of the main controller, two switching
modes of a
normal mode and a rapid mode are provided through matching of an Ethernet mode and an I / O mode, and resource synchronization realizes smooothness of role switching. A secondary controller is a double-serial-port controller, according to a mapping relation between main and secondary equipment, one block of redundancy equipment is added to the secondary equipment, so dual redundancy of a
serial communication network and equipment is realized. The mixed redundancy programmable
control system is advantaged in that cost is low, four-line mechanism and four levels of redundancy are employed to realize mixed redundancy, reliability is high, and different switching
modes satisfy different production technology requirements.