... 4-315KW ,0.01-650HZ ZY-A900 series of AC drives is our newest product of sensorless vector control ... pulse frequency, given MODBUS, PID adjusting and stage-speed control.Accessorial frequency Sourcegiven digit, given analog voltage, given ... external disturbanceDisplayLED nixie tube showing present output frequency, present rotate-speed (rpm), present output current, present output voltage, present ...