Why touch screen can control PLC?

Release time:

2018-11-14

PLC control itself, is through the control register D, input port X, soft relay state M and time relay T and other state variables to complete the change, so as long as you can modify the state of these variables, you can complete the control of the PLC, and the touch screen can communicate through the PLC's 232 or 485 port to complete these operations, so the touch screen can control the PLC.
Touch screen can be understood as a "soft dashboard and button plate", touch screen buttons actually work the same as the real button, it is the switch two states, they have an address, the reality of the button may be I0.0, while the touch screen button may be M0.0, such a conformation, representing A two-state switch variable, the reality of the button directly into the PLC through the external port, the essence is to determine a fixed address, and the touch screen is the same, to determine the address and PLC, the same, directly modified the state inside only.

Many times, PLC manufacturers do not open these addresses and variables in the communication port, but between the PLC and the computer has a program to edit the download window, said to touch screen manufacturers cracked this window, mastered its communication format, so it can directly communicate to modify the state of the PLC.

Guangzhou Quantchutong Industrial Co., Ltd.

Add：No. 13, Tongfu Road, Yahu Village, Renhe Town, Baiyun District, Guangzhou

Tel：

020-36533783 020-36533766

020-87576340
Phone：13580368109(Mr. Rao)

Fax：020-86258206

Email：gzhytouch@163.com

WEB：http//:www.touchposh.com