This book is the result of my research for my degree in industrial maintenance technology. It talks in particular about air compressors. Our work was to be able to supervise the start-up of compressors and control their operation from the control room. We start by presenting compressors in a general way, with emphasis on air compressors, we used the programming language "Grafcet" for this work. The simulation of the operation has been done with the software "Automgen". Thanks to this work, we have improved the production of electrical energy in the hydroelectric power station of Edéa in Cameroon. I leave it to you to appreciate the work and to bring points of amendment in order to perfect the next works.