... phase ac drive, frequency inverter, ac inverter, frequency converter, variable frequency drive - Constant torque type....2. Features OF VARIABLE SPEED DRIVE:sy8000 VARIABLE SPEED DRIVE HAVE Various ... ..Coal..Plastics.Printing and Dyeing..Cable..Washing.Water supply..Heating.Parameter: Itemdescription inputRated voltage, frequencySingle phase,220V,50Hz/60Hz; 3 phase ...