OPERATING INSTRUCTIONS Operation Undercarriage The undercarriage of the hydraulic excavator serves as a stable base and for travelling. The crawler tracks are driven hydraulically with oil motors and travel gearboxes. Undercarriage and superstructure are connected by means of a slewing ring.
Superstructure The superstructure accommodates the drive and part of the hydraulic and electrical equipment.
Demand control / Zero-flow regulation In the fine-control range, swivelling of the hydraulic pumps, and thus the variation of oil flow, are proportional to control lever and pedal valve travel. This means that during the work, the pumps supply only as much hydraulic oil as required to perform the working movement. In the neutral position of the control levers, the pumps are automatically swivelled to zeroflow.
Drive
These special features offer the following advantages:
The drive unit comprises diesel engines, pump transfer gearboxes, hydraulic pumps, hydraulic cylinders and hydraulic motors.
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reduced fuel consumption
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minimum power losses
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reduced temperature of the hydraulic oil
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greater service life of hydraulic pumps and diesel engines.
Hydraulic system All working and travelling movements are performed hydraulically. The movements are controlled by servovalves. The working commands are initiated by hand and transmitted to the valves via control circuits. The oil supply from the superstructure to the undercarriage is ensured by the rotor. The hydraulic system is overload-protected by pressure-relief valves. The hydraulic pumps are supplied with oil from a hydraulic reservoir.
Pump Managing System (PMS) The Pump Managing System (PMS) with overlimit regulation ensures optimum utilization of the installed or preset engine power. The electronic pump demand control prevents the machine from demanding more hydraulic power than the diesel engines can furnish. A microprocessor ensures that the hydraulic output power of the pump is optimally suited to the actual operation conditions.
Automatic engine speed reduction If the control pedals and control levers and thus the Servovalves are not actuated for a period of 10 seconds or more (programable), the speed of the engines is automatically reduced to idling. Thisfunction is a further contribution to fuel economy.
Electrical system The electrical system operates on 24 volts
The PMS box (load-limit regulator) is installed in a control cabinet in the driver's cab.
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BA RH30F(3 659 030.00)-EN
