Overview of the Underground Coal Mine Monitoring System

1. Introduction to Underground Coal Mine Monitoring System Underground Coal Mine Monitoring System Mainly used to monitor methane concentration, carbon monoxide concentration, carbon dioxide concentration, oxygen concentration, hydrogen sulfide concentration, ore dust concentration, wind speed, wind pressure, humidity, temperature, feed status, airlock status, fan status, local start and stop of ventilation fans and main fans, etc. The system realizes the functions of methane exceeding limit sound and light alarm, power failure, and methane wind and electricity interlock control.

2. Features of Underground Coal Mine Monitoring System Underground Coal Mine Monitoring System Underground coal mines are special working environments with flammable, explosive, flammable gases and corrosive gases, moisture, water mist, a large amount of mine dust, large fluctuations in grid voltage, serious electromagnetic interference, narrow spaces, and long monitoring distances. Therefore, the mine monitoring system is different from general industrial monitoring systems. Compared with general industrial monitoring systems, it has the following characteristics: ① Electrical explosion-proof; ② Long transmission distance; ③ The network structure should adopt a tree structure; ④ The monitored objects change slowly; ⑤ The grid voltage fluctuates greatly, and the electromagnetic interference is serious; ⑧ Repeaters should not be used.

3. Composition of Underground Coal Mine Monitoring System Underground Coal Mine Monitoring System It usually consists of sensors, actuators, substations, power boxes (or electrical control boxes), master stations (or transmission interfaces), host computers (including monitors), system software, servers, printers, large screens, and UPS power supplies. It consists of remote terminals, network interface cables, and junction boxes. 1) Sensors convert the measured physical quantities into electrical signals and have display and sound and light alarm functions (some sensors do not have display or sound and light alarm functions). 2) Actuators (including sound and light alarms and display devices) convert control signals into controlled physical quantities. 3) Substations receive signals from sensors and transmit them over long distances to the master station (or transmission interface) according to the pre-agreed multiplexing method. At the same time, it receives multiplexed signals from the master station (or transmission interface). The substation also has simple data processing functions, such as linear correction, overlimit judgment, and logical operations, processing signals input from sensors and signals sent by the master station (or transmission interface), and controlling the operation of actuators. 4) The power box converts AC power into the intrinsically safe DC power required by the system and is equipped with a battery to maintain a normal power supply for no less than 2 hours after a power failure. 5) The transmission interface receives long-distance signals sent by the substation and sends them to the host computer for processing; it receives signals from the host computer and sends them to the corresponding substation (the transmission interface also controls the sending and receiving of the substation and the modulation and demodulation of the multiplexed signals) adjustment, system self-check, and other functions. 6 The host computer generally selects an industrial control microcomputer or an ordinary microcomputer, with dual-machine or multi-machine backup. The host computer is mainly used for receiving monitoring signals, correction, alarm judgment, data statistics, disk storage, display, sound and light alarm, human-computer dialogue, output control, control print output, networking, etc.