The PLC control circuit for the cement mixer is shown in the figure.
This article only presents the control circuit diagram and ladder diagram of the PLC.
The main circuit controls the operation of the water pump, material pump, and mixing pump with overload protection through a variable frequency drive.
The water pump is a unidirectional motor,controlled bySB3 for jog control.
The material pump and mixing pump are bidirectional motors.
Among them, SQ1 and SQ2 are the upper and lower limit switches.
The working principle of the circuit and the PLC program will be explained in subsequent articles.