A FSD is a Fixed Speed Drive and a VSD is a Variable Speed Drive, with the main difference being the way the motor is controlled. A fixed speed compressor provides the motor with frequency and voltage at a consistent rate. A variable speed drive however automatically adjusts the motor speed and elements to the air demand.
Here at Atlas Copco we are market leaders in air compressors and are sure to have the most appropriate compressor based on your needs. To speak to someone about your options and if you require fixed speed or variable speed call us on 1800 023 469.