Screw Air compressor efficiency ratings depend on the operation state of the machine. Traditional machines are “constant pressure loaded/un-loaded operation” should the machine have no demand, the intake valve simply closes and the air end runs without producing compressed air. Even in this unloaded state, the compressor consumes power that is simply lost and wasted. The new generation of Frank VFD Air compressor system combined with advanced variable frequency drive technology that allows for “constant pressure variable operation mode” The operator can thus benefit from real no-load energy savings. Benefits of these systems are realized from the first day of operation as the energy savings are immediate. Frank series variable frequency speed drive compressor is researched and developed by a company based on the advanced European technology. This series of products are featured in stable running, easy operation, optimized protection function and long life. The human-oriented 3D design fully represents the new fashion of modern compressor technology in the world. The saved energy for using it for three years can be larger than its purchase cost