PLC BASED SCADA SYSTEM DESIGN FOR INSTANT MONITORING AND EARLY WARNING MECHANISM OF TOXIC GASES IN UNDERGROUND MINES

Abstract

In this study, a real-time toxic gas measurement and early warning mechanism is proposed to prevent accidents that may occur in underground mining facilities. Temperature, oxygen (O2), hydrogen sulfide (H2S), methane (CH4), carbon monoxide (CO) and dust density sensor data are read via Arduino Mega analog inputs. All sensor data is transferred to the PLC-SCADA (Programmable Logic Controller - Supervisory Control and Data Acquisition) system via ethernet in real time. Thanks to the designed SCADA screen, sensor values can be monitored instantly. In addition, it can be checked whether the system is alarm and whether the ventilation system works. According to the underground coal mine regulations, work cannot be done 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 permissible hydrogen sulfur ratio for 8 hours of operation is 20 ppm (0.002%). An early warning mechanism was created with the algorithm written taking these limits into consideration. The tests of the designed system were carried out in a laboratory environment and successful results were observed.