Design of Intrinsically Safe Repeater based on RS485 Communication for Coal Mine

As an important part of mine ventilation system, the intellectualization of air door is always a key link in digital mine construction. In the process of establishing a mine ventilation system including real-time monitoring, data transmission analysis, intelligent decision-making and real-time control, communication is an indispensable and important part. This paper designs an intrinsically safe mine repeater. As the main controller, STM32 single chip microcomputer can collect the signal of sensors and interact with the monitoring platform through RS485 communication. According to the command of the monitoring platform, the repeater outputs the switching value signal to control the actuator such as air door and alarm. In addition, repeater has a redundant RS485 interface which is used for signal forwarding and enhancement of other repeater or communication equipment to achieve good remote communication between monitoring system and field sensors. The product has been applied in practical engineering.