How to use wireless serial communication module to realize long-distance communication between touch screen and PLC?

串口无线,Simply put, wireless communication between devices is carried out through serial ports,The most common application is to replace the original wiredRS232、RS485通信.The wireless serial communication module is generally composed of a wireless transceiver chip and a single-chip microcomputer with a serial port,用户只要了解串口通信,不要了解复杂的无线通讯知识,Can complete the construction of wireless communication.

If you want to use the wireless serial communication module to achieve touch screen andPLClong-distance communication,The first step is to select both the touch screen and the touch screenPLC的通信模块.For example, we want to build Weiluntong touch screen and two setsS7-200Smart PLCwireless PPI 通信,It is necessary to choose and adapt to the Weiluntong touch screenS7-200Smart PLC接口、The module of the communication protocol is used to complete the communication construction.因为采用无线PPI协议响应速度快且不需要编程,只需要组态,所以采用PPIThis wireless communication will be more advantageous if the protocol network is established.那么,We can use SiemensPLC专用无线通讯终端DTD434M,作为实现无线通讯的硬件设备.

The communication scheme diagram is as follows：

接下来,We briefly sort out the hardware and software equipment needed for this wireless communication construction.

测试设备与参数：

●触摸屏：TK6071IQ × 1台

● 200SMART型号：CPU SR20 × 2台

●无线通讯终端：欧美系PLC专用无线通讯终端-DTD434MC × 3块

●数据线：西门子PLC专用485线 × 1根

●触摸屏数据线：触摸屏专用Rs485数据线 × 1根

●主从关系：1主2从

●通讯接口：Rs485接口（两线制）

●通讯参数：9600,8,E,1

●供电：9-24VDC

●传输距离：100米,500米,1KM,3KM,20KM

The main features of the wireless serial communication module:

●直接代替有线RS485方案,实现无线组网通讯;

● 全数字无线加密方式,保证数据安全可靠;

● 直流9~24V宽电源电压供电,平均工作电流小于50mA;

●通信接口：RS232/RS485;

●支持标准串口协议：Modbus RTU协议、PPI协议.

然后,We wire the equipment、After setting the parameters, the general selection test can be officially started.

接线方式：

1.Wiring the touch screen to the wireless device

第一步：将触摸屏专用Rs485数据线红色导线与DTD434MC的A端口相连接;将触摸屏专用Rs485数据线黑色导线与DTD434MC的B端口相连接

第二步：无线通讯终端设置开关中最后一位（K8-8）拨码开关向上

第三步：给无线通讯终端接入天线

第四步：全部接线结束后,给触摸屏与无线通讯终端供电

2.PLCWiring to wireless devices

Weilun is realized by touch screenPPI主站：

打开“Wei Lun Tong touch screen1主2从PPI例程.emtp”

系统参数设置;触摸屏画面制作;1号从站的I点设置;1号从站的Q点设置;2号从站的I点设置;2号从站的Q点设置.

西门子PLC实现PPI从站：

PLC参数设置;设置PLC地址（设置一台PLC地址设为1,另外一台PLC地址设为2.选择“参数—模块参数—485串口”）;CPU模式（选择：RUN,将程序下载到PLC里面）

无线通讯测试：

1. 触摸屏输出信号

通过触摸屏上面的按钮给1号从站Q点信号,看200SMART对应的Q点是否有亮,如果点亮,表示通讯正常.

2. PLC输入信号

通过外部给1号从站I点信号,看触摸屏对应的点是否有亮,如果点亮,表示通讯正常.