The PFSK164 analog input module is an intelligent device mainly used to collect and transmit analog signals from remote sites to the computer. These analog signals usually represent parameters such as voltage, current, frequency, etc. of things, which are continuously changing arbitrary values. The module uses the RS-485 bus as a data communication line and has the function of converting analog quantities to 485. It can input multiple analog quantities to the module at the same time and transmit them to the computer through the RS-485 bus. The analog input module uses the MODBUS RTU protocol to achieve unified docking with industrial field data collection, and is also very convenient to program. At the same time, it supports multiple acquisition ranges and various configuration software docking, and can be directly connected to the configuration software. In addition, the analog input module also has a secondary filter circuit, which can improve circuit design and reduce interference. This kind of module is widely used in various occasions where analog signals need to be collected and processed, such as analog input of PLC and motion controller, current detection, voltage detection, temperature detection, etc. The use of analog input modules can achieve real-time monitoring and precise control of these parameters, improving the automation and operating efficiency of the system. Overall, the PFSK164 analog input module is a powerful, easy-to-use smart device that is of great significance for industrial automation and control systems.