EH4000ACII - Hitachi Construction Machinery

AC Drive AdvantageHitachi AC drive technology providessuperior truck performance with highertop speeds, better gradeability andstronger retardation.Hitachi inverter modules provide highrigid truck controlability and efficiency.The Hitachi AC wheel motors do nothave commutators and brushes,which improves truck performance byproviding reduced maintenance costs,higher truck availability and highertravel speeds. These advantages resultin more productivity and lower costsper tonne.Hitachi AC drive systems also powerelectric train locomotives world wide.Water Cooling PumpAC Control CabinetGrid MotorRetarding Grid BoxAlternator BlowerWheel Motor BlowerAlternatorAC Wheel MotorFull Retarding CapabilityThe AC Drive Wheel MotorsAC Drive ControlRimpullRimpullDrivingAC DriveDrivingRetardingSpeedRetardingBrake Blending, which combinesservice braking with electric retarding,is applied automatically through the ACdrive control system to stop the haulerwhen travel speed is below 0.5 km/hr.Therefore, with the exception ofemergencies, the driver can stop thetruck using the retarder pedal only,resulting in easy machine operationand longer time between brake serviceintervals.Auto Cruise Control keeps vehiclespeed constant within the set range bylimiting the minimum vehicle speed.DC DriveSpeedHitachi AC drive systems provide morerimpull than comparable DC systems.Full retarding capability means the truckcan be fully stopped without applyingthe service brake pedal.The Hitachi Dual Path Epicyclic Planetarydesign provides high efficiency and easymaintenance.Allowing the 1st (outer) planetary carrierto travel at wheel speed provides loweroperating temperatures.Better component and lubricant life is theresult of an inverter controlled lubricantcirculation system that includes lubricantcooling and filtration.Auto Retarding Control keeps vehicledownhill speed constant within the setrange by limiting the maximum vehiclespeed.