Fri August 15, 2008
Aggregate Equipment Guide
The newest and largest models of Hitachi trucks are the electric-drive EH3500ACII and EH5000ACII trucks.
The new EH3500ACII truck uses the Hitachi AC-Drive system for better performance, higher availability, and significant reductions in maintenance and operating costs, according to the manufacturer.
A new Hitachi-made controller monitors truck systems and replaces multiple outsourced controllers. A simple flat-panel dashboard consists of a 10.4-in. (26.4 cm) LCD monitor that eliminates all independently placed gauges and lights. The philosophy behind the monitor in the trucks is the same as the Dash-6 excavators — it allows for quick troubleshooting on the machine to reduce costs and downtime.
The EH5000ACII uses the Hitachi/Siemens IGBT AC-Drive system. This upgrade provides for improved gradeability and productivity over the previous GTO system due to improvements in component cooling capacity and improved rimpull characteristics, according to the manufacturer.
Hitachi is not new to the electrical drive system business, with hundreds of drive systems running in applications varying from bullet trains and large production plant automation systems to electrically powered mining shovels and backhoes. Hitachi has experience with electrical drives in the mining industry, both with its rigid-frame mining trucks and hydraulic shovels and backhoes.
In addition, the two AC-powered trucks maneuver easily in tight spaces and comfortably handle the haul road with steady speed on grade. AC-retarding to near-zero ground speed is coupled with a service brake blending feature that applies the hydraulic service brake to easily bring the hauler to a complete stop and reduce brake wear. The new high-tech ROPS/FOPS cab uses a three-point rubber ISO-mount to minimize vibration.
This story also appears on Construction Equipment Guide.