Abstract: The air compressor that provides power to pneumatic equipment such as air picks and air drills in coal mines has always operated in a traditional manual duty mode. The high noise environment not only harms the physical and mental health of employees，but also is not conducive to equipment trouble⁃ shooting. In order to solve this problem，a set of automatic monitoring system with multiple ground air com⁃ pressors and Siemens S7-300 series PLC as the control core is designed to realize the centralized control and intelligent operation of the air compressor room，so as to realize the goal of unattended air compressors.

Key words: PLC control, smart mine, air compressor monitoring