... .1-600hz 5.Easy install 380v 0.4kw 3 phase ac input and output frequency converter with vector control Introduction of ... VF curve. This apply to the situation that one frequency inverter drives multiple motors, such as fan, water pump, engraving machine, injection ... ) Open-loop vector control: Steady speed with high precision, wide range of speed governing, as the speed ratio is 1:200 ...