Although domestic products can be used, they are not stable. At the same time, there is a baud rate problem in PC/PPI communication. You can find the internet. It should be said that the connection between the computer and the programming line should be normal, but you can also check that if you use an ordinary PC/PPI communication line,
It has six dual in-line switches, which are usually closed. When searching for PLC, you should see an indicator light on the programming cable flashing all the time, indicating that the computer is sending command data through the programming cable. If it doesn't flash,
The local connection setting of the programming cable is incorrect. There is also a baud rate problem, which is set to search all baud rates. In addition, if each PLC has a program, it is best to set the running switch of PLC to $ TERM position during communication.
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When PLC is in formal operation, it doesn't need a programmer. Programmers are mainly used to compile, store and manage user programs, and send them to PLC for monitoring and fault detection during debugging.
S7-200 series PLC can use a variety of programmers, generally divided into simple and intelligent. The simple programmer is pocket-sized, simple and practical, and low in price. It is a good tool for field programming and monitoring, but its display function is poor.
It can only be input in the form of instruction list, which is not convenient to use. The intelligent programmer uses the computer for programming operation and loads the special programming software into the computer.
On-line monitoring can be realized directly by programming with ladder diagram language, which is very intuitive and powerful. The special programming software of S7-200 series PLC is STEP7-Micro/WIN.
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