1. The touch screen controls the frequency inverter via PLC
(1) At present, the general control of the frequency inverter needs to use PLC to communicate with the frequency inverter, read the information of the frequency inverter, and then the touch screen to communicate with the PLC, in order to complete the control of the frequency inverter start, stop, and monitor the operating frequency, current, voltage and other functions of the frequency inverter.
(2). Touch screen by PLC control frequency inverter method
The touch screen is connected to the PLC programming port, and then a 485 interface is extended on the PLC, and then the PLC and the frequency inverter communicate through 485. These two communications can communicate without affecting each other, and then write the corresponding program according to the need, so that the touch screen through the PLC to change the frequency of the frequency inverter.
2.Without PLC, touch screen directly controls the frequency inverter
In order to make the frequency inverter run, there must be two conditions, that is, the start signal and the frequency signal, so the essence of the touch screen control frequency converter is to realize the start signal and frequency signal of the frequency converter on the touch screen. The touch screen and the frequency converter are connected through communication, so the problem boils down to the touch screen as the communication master station and the frequency converter as the slave station to establish a connection. The frequency converter has RS485 interface, which supports the MODBUS protocol, therefore, we only need to establish a MODBUS slave station in the touch screen, below we use a practical case to demonstrate to you, the method and steps of directly controlling the frequency converter with the touch screen.
3.The touch screen directly controls the operation steps of the frequency inverter
(1）making communication line, the connection of touch screen and frequency inverter;
(2) Touch screen communication parameter Settings;
(3) Touch screen operation screen production;
(4) The master station controls wiring and commissioning of the slave station.
