西门子SIEMENS 6ES7972-0BA60-0XA0 PROFIBUS 总线连接器

西门子SIEMENS 6ES7972-0BA60-0XA0 PROFIBUS 总线连接器

规范的接线及走线，弱信号要尽量与强电信号分开走   模拟量信号线要采用单端接地方式，通信线要采用双端接地方式   

热电偶要采用绝缘式的传感器   PLC的供电电源尽量采用隔离变压器   防止直流电源的负端与交流电的零线或大地有任何的接触 ,所有直流电源要注意要共负端，不共可能会造成采样不稳定，因为没有共同的参考地   

231-0HC或235-0KD模块容易采共模电压的干扰，把信号的输入的负端与24VDC的负端短接，可以有效地防止这种干扰   通信线要注意终端电阻的使用   CPU的通信口为非隔离口，与其它设备（变频器）等通信时好加光电隔离器

Standard wiring and wiring, weak signals should be separated from strong signals as far as possible. Analog signal lines should be single-ended grounded, and communication lines should be double-ended grounded

Thermocouple to use insulated sensor PLC power supply as far as possible to use isolation transformer to prevent the negative end of the DC power supply and AC neutral line or ground have any contact, all DC power supply should pay attention to the common negative end, not common may cause sampling instability, because there is no common reference

231-0HC or 235-0KD module is easy to take the interference of common mode voltage, the negative end of the signal input and the negative end of 24VDC short, can effectively prevent this interference communication line should pay attention to the terminal resistance of the use of CPU communication port is non-isolated port, and other equipment (frequency converter) and other communication good photoelectric isolator