... n pumps are interchanged to connect with the drive for a fixed period of time. After the interchanging time, frequency-conversion pump will be ... seconds.Torque ElevatingManual Torque Promotion 0.1%~30.0% (V/F)V/F Curve3 kinds of modes: beeline type, square ... analog voltage, given analog current, PI adjusting and stage speed control.Protection FunctionInput out-phase, input under-voltage, over-voltage ...