OM5037 06/06 Specifications - Section 50 Page 50-1 MAJOR COMPONENT DESCRIPTION The Komatsu model 730E dump truck is an electric drive, off-highway, rear dump truck whose gross vehicle weight is 324,322 kg (715,000 lbs) rated for a nominal payload of 185 t (203 tons). ENGINE POWER STEERING The Komatsu 730E dump truck is powered by a Komatsu SSA16V159 engine rated at 2000 HP (1492 kW). The Komatsu 730E dump truck is equipped with a full-time power steering system, which provides posi- tive steering control with a minimum of effort by the operator.
The system includes nitrogen-charged accumulators which automatically provide emer- gency power if the steering hydraulic pressure is reduced below an established minimum. ALTERNATOR (GE GTA-22) The diesel engine drives an alternator mounted in- line with the engine. The Alternating Current (AC) output of the alternator is rectified to Direct Current (DC) and sent to the DC drive wheel motors. DYNAMIC RETARDING WHEEL MOTORS (GE 788) Dynamic retarding is used to slow the truck during normal operation or control the speed coming down a grade.
The dynamic retarding ability of the DC elec- tric system is controlled by the operator through the activation of the retarder pedal in the operator’s cab and by setting the RSC (Retarder Speed Control). Dynamic retarding is automatically activated if the truck goes to a preset overspeed setting. The output of the alternator supplies electrical energy to the two wheel motors attached to the rear axle housing. The two wheel motors convert electrical energy back to mechanical energy through built-in gear trains within the wheel motor assembly. The direction of the wheel motors is controlled by a for- ward or reverse hand selector switch located on a console to the right side of the operator.
BRAKE SYSTEM The wheel service brakes are caliper/dry disc brakes applied by an all hydraulic actuation system. Depressing the brake pedal actuates wheel-speed single disc front brakes and armature-speed dual disc rear brakes. The rear brakes can also be acti- vated by operating a switch on the instrument panel. BLOWER The blower supplies cooling air for the rectifiers, AC alternator, and to both wheel motors, where it is then exhausted to the atmosphere. OPERATOR'S CAB All wheel brakes will be applied automatically if the system pressure decreases below a preset mini- mum.
The operator's cab for the Komatsu 730E dump truck has been engineered for operator comfort and to allow for efficient and safe operation of the truck. The parking brake is a caliper/disc type, mounted on each rear wheel motor, and is spring-applied and hydraulically-released with wheel speed application protection (will not apply with the truck moving.) The cab provides for wide visibility, with an integral four-post Rollover Protective Structure/Falling Object Protective Structure (ROPS/FOPS), and an advanced analog operator environment.
It includes a tinted safety-glass windshield and power-operated side windows, a deluxe interior with a fully adjustable seat with lumbar support, a fully adjustable/tilt steer- ing wheel, controls mounted within easy reach of the operator, and an analog instrument panel which pro- vides the operator with all instruments and gauges, which are necessary to control and/or monitor the truck's operating systems. SUSPENSION Hydrair®II suspension cylinders, located at each wheel, provide a smooth and comfortable ride for the operator and dampens shock loads to the chassis during loading and operation.