PLC and SCADA based automation system design for underground mine facilities

In this thesis, a PLC and SCADA-based toxic gas measurement system and early warning mechanism are designed with the aim of increasing occupational safety and efficiency in underground mining facilities and reducing possible accidents. The toxic gases carbon monoxide (CO), methane (CH4) and hydrogen sulfide (H2S), as well as temperature, oxygen (O2) and dust density values are read by analog inputs of the Arduino MEGA board via the relevant sensors. Sensor data is transferred to the PLC-SCADA system in real-time via Ethernet. All sensor values can be monitored instantly on the designed SCADA screen. In addition, it can be checked on the same screen whether the system is in alarm mode or not and whether the ventilation system is working. According to the underground coal mine regulations, it is not appropriate to work in places where the mine air contains less than 19% oxygen, more than 2% methane, more than 50 ppm (0.005%) carbon monoxide and other hazardous gases. The highest allowable hydrogen sulfide content for 8 hours of operation is 20 ppm (0.002%). Thanks to the algorithm prepared taking these rules into consideration, an early warning mechanism was created. All sensors have been tested individually in a laboratory environment and the necessary calibration procedures have been completed. Later, the tests of the designed PLC-based SCADA system were carried out in a laboratory environment. With the SCADA system, the ambient temperature, the concentration of oxygen and toxic gases in the mine air, and the amount of dust in the environment are successfully displayed in real-time. Laboratory tests for the early warning mechanism also completed successfuly.