The RS485 and MON (using RJ45 connector) ports are provided by the CMU or MCU of S7700&S9700. The two ports are reserved for function expansion in future.

For example, if the device supports external PoE, the RS485 port connects to the external PoE power supply.

If the device supports external environment monitoring, the MON port connects to the sensors such as temperature sensor and smoke sensor as an input port for environment monitoring.

The preceding functions are used as examples to describe the port functions, and they are not supported by S7700&S9700 currently.