Mine Electrical Systems, Part 2-Alternating Current Systems [History]

Underground coal mining presents unique challenges for the safe application of electric power distribution and utilization. Power equipment and electric machinery in most industries are located in stationary, permanent facilities and are not subjected to extreme operating conditions. However, coal mining is an ever-changing process in which electrically driven, portable, and mobile mining equipment is regularly moved or self-propelled. As a result, power equipment and cables are also moved regularly. The confined spaces and rough floor conditions of mine openings are not conducive to the gentle handling of equipment and power cables. Furthermore, the coal mining environment can be dusty, wet, and even explosive.