SYSTEM / Controller Pump Control Pump Flow Rate Control Delivers oil required for the actuator according to the control lever stroke from the main pump. Speed Sensing Control Controls the pump flow rate in response to engine speed changes due to variations in load so that the engine output can be utilized more efficiently. (Engine stall is prevented when the machine op- erates under adverse conditions such as operat- ing at high altitude.) Overheat Prevention Control Reduces maximum flow rate and suction torque of the main pump, reduces the engine load and prevents overheating when temperature of cool- ant or hydraulic oil increases beyond the specified level.
Attachment Mode Control (Optional) Limits the upper of maximum flow rate of pump 2 and controls the appropriate flow rate for the at- tachment when operating the attachment with the work mode in attachment mode. Counterweight Removal and Installation Control (Optional) Applies back-pressure to the main relief valve, increases main relief pressure and the hoist / lower power improves. Or, Controls pump delivery flow rate and makes fine operation easy.
Fan Pump Flow Rate Control Controls delivery flow rate of the fan pump ac- cording to boost temperature (intake air tem- perature passing by the intercooler), coolant temperature, hydraulic oil temperature and intake air temperature), and controls fan rotation speed in order to make temperature of oil cooler, radiator and intercooler appropriate. Pump Learning Control Detects pressure, which is necessary to pump control, when the pump control solenoid valve is activated. E Mode Control Decreases the pump suction torque to 85 % in order to reduce the engine load and improve fuel consumption rate.
Engine stall is prevented when inferior fuel is used or the machine operates un- der adverse conditions such as operating at high altitude. Horsepower Control Controls delivery flow rate of each main pump and uses engine power effectively so that sum of pump torques divided to two main pumps and fan pump does not exceed the engine output torque. Relief Flow Rate Reducing Control Controls hydraulic energy loss and prevents hy- draulic oil temperature from rising.
(Flow Rate Reducing Control (Relief Cut Off)) Swing Horsepower Reducing Control Decreases delivery flow rate of main pump 2 in- cluding the swing circuit, increases delivery flow rate of main pump 1 and uses the engine power effectively when the swing control lever is oper- ated and the pressure sensor (swing) detects swing pilot pressure. T2-1-6