Basic method for PLC transformation of machine tool electrical system - Database & Sql Blog Articles

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The use of plc to transform the electrical system of the machine tool greatly simplifies the electrical circuit. The design method is that each electrical component is directly connected to each input and output port of the PLC, the connection relationship between the components, and the state of each coil are determined by a logic program, and there is no direct series or parallel connection between the components, so The line is simple, and the logical relationship is determined by the program, which is easy to maintain and design.
1. Electrical components and PLC hardware connection The connection between the electrical components and the PLC is mainly to connect the switches, buttons, relay contacts, contactor auxiliary contacts, etc. required by the control circuit to the input port of the PLC, and determine each The port number corresponding to the contact, and the multiple contacts of one component generally only need to be connected to one input port. The energy-consuming components such as the relay coil, the contactor coil, the solenoid valve coil, the indicator light, and the illumination lamp are connected to the output port, and then the input and output port assignment tables are established, and each port number is an important logic quantity for the logical operation of the logic program.
2. Logic programming After connecting each component to the port of the PLC, it is also necessary to write a logic program to determine the logic conditions for the power and power loss of each output port, thereby controlling the state of the corresponding energy-consuming components of each output port. The logic program should be written according to the control requirements of the machine tool and the logic relationship in the original relay control circuit. When the PLC is running, it can collect the state of each input port, perform logic operation according to the established logic program, and then control each output port to make each coil connected to the output port get power or power off, thereby controlling the motor and hydraulic system. Work with other electrical components, that is, to replace the serial and parallel wiring between the original components by developing logic programs.
The above method can be used to complete the control requirements required for the machine tool work. Combined with the functional characteristics of the PLC, it can be considered that the machine tool fault self-diagnosis can be realized by writing a logic program or adding a small number of components as needed on the basis of the existing components. It is very advantageous to improve the reliability, efficiency, maintainability of the machine tool and avoid further accidents.