注意事项

在PLC和变频器同时使用的自控系统中，应该着重注意以下事项：

1、PLC供电电源与动力系统电源(变频器电源)分别配置，且PLC的供电应该选择隔离变压器。

2、动力线尽量与信号线分开，信号线要做屏蔽。

3、无论是模拟信号输入还是模拟信号输出，模拟量通道一律使用信号隔离模块。

4、PLC程序里做软件滤波设计。

5、信号地与动力地分开设计。

matters needing attention

In an automatic control system where PLC and frequency converter are used simultaneously, the following precautions should be emphasized:

1. The PLC power supply and power system power supply (frequency converter power supply) should be configured separately, and the PLC power supply should choose an isolation transformer.

2. The power line should be separated from the signal line as much as possible, and the signal line should be shielded.

3. Both analog signal input and analog signal output use signal isolation modules for analog channels.

4. Design software filtering in PLC programs.

5. Separate the design of signal ground and power ground.